Bridging Genomics and Education
by Elena L. Grigorenko - March 26, 2007
This article attempts to link advances in genomics to education and to show why understanding and incorporating concepts and recent findings from genomics is extremely important for the future of education. Because genomics refers to studies of the whole genome and how it functions as a system in an environment, and because schooling represents a crucial type of environment in development, it appears to be sensible to explore possible links between genomics and education. I suggest that educators might want to pay close attention to developments in genomics to (1) enhance their understanding of the dynamics and complexities of human development; (2) provide a basis for strengthening their attempts to individualize education by capitalizing on every child’s strengths and minimizing weaknesses; and (3) prepare themselves for new paradigms of child rearing and schooling. Genomics is already revolutionizing the way medical care is delivered and distributed; it will inevitably affect children’s developmental trajectories by introducing more pharmacological and behavioral therapies. Educators will need to understand the impact of these changes on children in the classroom, where American children spend a large portion of their formative years.
Outside school, Abby likes music, sports, and arts. However, Abby struggles in school and has special learning needs. School is very hard for her, and she knows that for some reason she cannot learn the way her peers do. Abby finds it difficult to follow new material presented orally and in print, although she sees that her classmates have no problem grasping new concepts from lectures and textbooks. When asked to work independently, she gets confused and lost, is embarrassed to ask questions, and finds it easier to pretend she understands than to keep asking for explanations, especially in front of the whole class. Sometimes Abby makes grammatical errors in her speech and in writing, which is also very challenging for her: Abbys thoughts crowd her head but she finds it difficult to express them on paper. In addition, she often misunderstands conversations among her peers and is teased. Yet, Abby enjoys math, as long as she doesnt need to deal with word problems. Nevertheless, because of her difficulties with language, Abby hates school. She is frustrated, anxious, and depressed about learning.
Abbys story is no doubt quite familiar to many educators, especially those who work with children with special educational needs. In fact, pretty much any student with a learning difference, which in Abbys case is related to her language disability, can tell a similar story. Abby started school just like any elementary school child, happy to be there and ready to learn, but as the reading load grew heavier and more demands were placed on her verbal comprehension and reading skills, her joy in learning slowly evaporated and she became disengaged and frustrated. Her low achievement decreased her motivation to learn and work hard, which in turn resulted in lower achievement; her cycle of academic failure had formed.
Although this example is recognizable to many educators, what might be less familiar is how current developments in the field of modern biological sciences, specifically genomicsthe study of genes and their function in the context of the whole genomemay shed light on how this cycle forms.
The Importance of Bridging Economics and Education
The completion of the Human Genome Project in 2003 (http://www.ornl.gov/sci/techresources/Human_Genome/home.shtml) and subsequent work on genetics have resulted in the discoveries of genes and gene variants associated with typical and atypical human conditions (for a review, see a special issue of Nature Neuroscience, 9, 2006). Sequencing the genomes of humans and approximately 180 other organisms led in part to the detailed characterization of specific genes and their expression patterns (i.e., translation of a particular DNA sequence into a specific protein), which substantiated the formulation of one of the main principles of modern genetics: DNA is both inherited and sensitive to environments. It is not merely a function of one or the other.
DNA exists in the increasingly distal environments of the nucleus, cell, organ, organism, family, society, and culture. All of these environments influence how DNA is regulated, transcribed, and transmitted from generation to generation. Research on DNA is ongoing and producing burgeoning volumes of new genetic information as well as the crystallization of the field of genomicsthe study of genes and their function. It is difficult to stay on top of findings from these studies, even for someone directly involved in the field. The rapid flow of new information can be overwhelming. The volume and complexity of the information often results in misconceptions and misunderstandings of interpretations of the latest genomic findings (Rutter, 2006; Rutter & Plomin, 1997).
Despite multiple attempts at resolution (Sternberg & Grigorenko, 1997), the naturenurture controversy has not yet been put to rest, at least when it comes to education. The continuation of this controversy is due in part to naïve associations of DNA with concepts of biological determinism and the equation of genetic with fixed and unchangeable. Much of the public, understandably, is reluctant to view DNA as a significant source of variance in academic achievement, school success, and the development of competencies. People often feel much more comfortable attributing school failures to bad teachers, poor achievement motivation, or vague concepts of ability. Many educators and psychologists are also leery of accepting DNA as a basis of individual differences observed in school settings; concerns with overstating the role in schooling of biology in general and of genes in particular are quite prevalent in the educational literature (Miller, 2000). But biologists have long accepted the idea that behavioral variation is an outcome of genes and environments co-acting and interacting together. And, educational researchers have long studied children in their school environments. Therefore, it seems profitable for educators and biologists to work together in their study of nature and nurture.
Here I offer additional thoughts on the naturenurture controversy in light of what weve learned since the late 1990s and attempt to show why understanding and incorporating concepts and recent findings from genomics is extremely important for the future of education. I suggest that educators should pay close attention to developments in genomics to (1) enhance their understanding of the dynamics and complexities of human development; (2) provide a basis for strengthening their attempts to individualize education by capitalizing on every childs strengths and minimizing weaknesses; and (3) prepare themselves for new paradigms of child rearing and schooling. Genomics is already revolutionizing the way medical care is delivered and distributed; it will inevitably affect childrens developmental trajectories by introducing more pharmacological and behavioral therapies. I suggest that these therapies will be incorporated into the lives of children in the developed world, and, because schooling is an essential component of their lives, they will be brought to school through interactions between the school and family and among children in classrooms. Correspondingly, it might be wise for educators to understand the impact of these changes on behavior and academic performance of children in the classroom, where American children spend a large portion of their formative years.
Because schooling is one of the major cultural inventions of humankind, the school environment has always been and will always be a major player in modifying childrens gene expression. There is suggestive evidence that impoverished environments suppress gene-related variation in cognition, whereas enriched environments enhance such variation. For example, Turkheimer and colleagues (Turkheimer, Haley, Waldron, D'Onofrio, & Gottesman, 2003) estimated heritability of IQ in a sample of 7-year old twins from the National Collaborative Perinatal Project. The project participants were highly diverse in terms of socioeconomic status (SES), with several families living near or below the poverty level. The researchers reported that heritability of IQ in this sample varied dramatically across SES levels: In impoverished families, heritability estimates were close to 0 and shared environment was the main source of individual difference, whereas in affluent families, the result revealed almost the opposite profile. What used to be viewed as a black box of childrens individual differences will gradually be replaced by a summary of the roughly 24,500 genes (Pennisi, 2003) carried by these children and their differential patterns of expression in different environments (Foerstner, von Mering, Hooper, & Bork, 2005). Genomics is on its way to characterizing every individual in terms of his or her genetic script (see below), but it is environments, especially schools, that will determine the realization of this script by its possessor into the performance of a lifetime (Lewis, 1999), where every individual plays out his or her genetic script in a unique way.
Similar to how the Human Genome Project broadened and increased the importance of genetics and genomics in healthcare (Epstein, 2005, 2006; Guttmacher, Jenkins, & Uhlmann, 2001; Khoury, 2003; Weston & Hood, 2004; Willard, Angrist, & Ginsburg, 2005), recent advancements in genetics and genomics associated with our understanding of academic abilities and disabilities (Fisher & Francks, 2006; McGrath, Smith, & Pennington, 2006) will magnify the role of genetics and genomics in education. Genomics is about comprehending the complex interactions of multiple genes (the genome) and environments; because the genome substantially contributes to individual differences in abilities and disabilities, and because school is one of the major environments in which almost all children are immersed for hours on end for many years, it is important to understand the role of schooling in general and different school environments in the manifestation of different genetic predispositions, and to translate these findings into informed pedagogical tactics and strategies. In the medical sciences, there are numerous examples of how environments can strengthen or lessen genetic risk factors for health, for example through the impact of diet and sun exposure (Chakravarti & Little, 2003). Similarly, there is a growing body of evidence in psychology and psychiatry indicating how adverse life circumstances (e.g., maltreatment in childhood) can magnify genetic risk factors (e.g., the impact of a particular risky genetic variant) and result in maladaptive behaviors (Caspi & Moffitt, 2006; Rutter, 2007). Although no research literature on how particular educational pedagogies trigger or prevent the expression of genetic risk factors related to cognitive disabilities has yet been published, such literature is actively in the works in a variety of research laboratories both in this country (e.g., Institute for Behavior Genetics at the University of Boulder, Colorado) and abroad (e.g., Institute of Psychiatry in London). Such research aims to provide a set of recommendations, based on a constellation of genetic risk factors, for the most protective/remedial educational approaches (similar to how nutritionists prescribe the most appropriate diets based on a genetic risk profile for a variety of health conditions).
In anticipation of the emergence of this knowledge, I offer an opinion that educators (broadly defined as professionals concerned with education) would be wise to prepare to deal with the infusion of genomics knowledge into their everyday practice. If not in the vanguard of the dissemination and popularization of this knowledge, teachers will find themselves left behind in a process they could be leading.
This is not to say that genomics must now be added to the already-long list of what a teacher needs to know. No single classroom teacher can be expected to know everything. The quantity of knowledge constantly increases in modern society across multiple domains of our culture, including teaching. As a result, there is a greater demand for team-based approaches. In school, team-based approaches are chiefly targeted at increasing the individualization of education, especially in special education. Bridging genomics and education might then mean including genomics experts on teams of specialists shaping childrens education. In other words, a teacher would not be expected to master a new field of knowledge or to be an expert in it. But teachers might want to include this knowledge in decisions about individualized education and referrals to educogeneticists or educogenomicistsprofessionals whose knowledge of both education and genetics/genomics allows them to make informed recommendations to both schools and families. As illustrated below, such a specialist might be instrumental in breaking Abbys cycle of school failures and improving her educational outcomes. Abbys genetic test results might be interpreted in light of the research on the effectiveness of different educational techniques. As a variety of these techniques are researched for their efficacy in groups of children with different profiles of genetic risk, educogenomicists will be able to analyze the results of genetic testing and recommend an individualized pedagogical approach for children. This does not necessarily mean that Abby will need individualized education, but rather that decisions about programs for Abby (in the regular classroom, small groups, or one-on-one) could be informed by the knowledge of her genetic risk factors.
This brief set of notes is structured around three main themes. First, I discuss a selected set of concepts from genetics and genomics to support my argument that knowledge of genomics is relevant to educators. Second, I discuss genomics developments in the field of medicine. Third, I hypothesize how genomics knowledge may affect American schooling in the not-too-distant future. Because neither psychology nor education has yet produced evidence on this topic, I illustrate various points from the field of medicine, which is rich with relevant examples.
Inherited and Deterministic: Correcting the Metaphor
It is important to stress that inherited does not mean deterministic. In fact, this statement or a variation on the theme is seen in all major textbooks on behavior genetics (Plomin, DeFries, McClearn, & McGuffin, 2003) or molecular genetics (Klug, Cummings, & Spencer, 2006) and psychology (Sternberg, 2004). The genome is influenced by both inherited and environmental factors. What is inherited is a set of DNA material assembled probabilistically from the DNA of an organisms parents. Inherited DNA is characterized by two sets of parameters: It is (1) species specific (i.e., humans inherit DNA sequences characteristic of humans and not of other species), and (2) ancestor specific (i.e., inherited DNA is assembled from the material available through the parents, and thus contains polymorphisms, or points of variation in its sequence, that are transmitted from generation to generation). Genetic polymorphisms (also referred to as genetic variants) determine patterns of gene expression, variation in proteins, and protein activity. These protein-based variations constitute the basis of individual differences in a variety of functions ranging from the most basic (e.g., metabolism) to the most complex (e.g., wisdom).
Surprisingly, genetically, humans are not very different from their closest relatives, common chimpanzees (Pan troglodytes). A draft of the entire Pan troglodytes genome was made public in 2005 (Chimpanzee Genome Resources, http://www.ncbi.nlm.nih.gov/genome/guide/chimp/); we now know that DNA sequences of human and chimpanzee genomes differ by only a small
fractionjust a few percent (Li & Saunders, 2005). Similarly, when two people are compared with each other, their DNA sequences overlap by 99.9% (http://www.chr7.org/news.php). So, where do the behavioral differences between a human being and a common chimpanzee, and between different human beings, originate?
The current hypothesis is that the observed diversity between and within species comes from the way the genetic script interacts with the environments in which it exists (Bateson et al., 2004). One metaphor describes the genome as a cache of information. As mentioned earlier, it is estimated that the genome consists of approximately 24,500 genes, which are responsible for the production of ~100,000 proteins (Pennisi, 2003). Thus, there is no one-to-one correspondence between genes and proteins. One can only imagine the complexity of this information when thinking about even a portion of the interactions unfolding among these genes, proteins, metabolites, and the like. And, on top of this complexity, it is clear that human behaviors, typical and atypical, are caused by the interaction of these biological agents with peoples varying nucleic, cellular, bodily, familial, social, and cultural environments. Thus, with the exception of rare severe genetic disorders, what is inherited is not deterministic but rather only probabilistic. DNA variants are risk and protective factors that predispose their carriers for developing but not necessarily manifesting both typical and atypical physical characteristics as well as behavior traits and developmental and health conditions. Environment in general and schooling in particular are important for diminishing potential detrimental consequences and enhancing potential beneficial impacts of genetic variants. For example, it is possible that high-level engagement in academic activities affects characteristics of neuronal connectivity in the brain by recruiting some epigenomic mechanisms (i.e., heritable characteristics that do not change the DNA structure, but do change DNA transcription, such as methylation).
The idea that inherited DNA variants are predisposing, not determining, is a gateway into the next very important concept in modern genetics: penetrance, which is the probability of expressing a phenotype given a genotype. Penetrance of a genetic variant refers to the frequency with which the phenotype (e.g., an observable characteristic of an individuala particular behavior, trait, disease) it controls is observed in people who carry this variant. Penetrance is described as either complete or incomplete. For example, individuals who carry the gene for tuberous sclerosis have an 80% chance of expressing the disorder (i.e., incomplete penetrance). Penetrance also has an age dimension; it increases as people age. For example, among all gene carriers for myotonic dystrophy, 20% express the gene phenotypically (i.e., show the symptoms of the disorder) by age 15, whereas 80% express it by age 60.
Although penetrance is a concept used at the population level (i.e., we need to know how many individuals carry a detrimental genetic variant and how many people manifest this variant), it gives us even more appreciation of the probabilistic nature of genetic influences. For example, there are more than 450 detrimental variants in the PAH gene that cause the rare disorder phenylketonuria (PKU, a genetic disorder involving the metabolism of phenylalanine), which causes a type of mental retardation.
However, the penetrance of these variants is incomplete, indicating that not all individuals who carry these mutations manifest the disorder. The accumulation of genetic data on various disorders and their genetic causes suggests that the more penetrant the variant, the less frequently it is observed in the general population. Correspondingly, the more frequent the variant is in the general population, the lower its penetrance, and hence its deterministic impact. Often, what is needed for these low-penetrant common variants to act is an interaction with the environment.
To illustrate, genetic variation in the NAT2 gene can result in more rapid enzyme metabolism (caused by so-called rapid polymorphisms) as well as slower enzyme metabolism (caused by so-called slow polymorphisms). Carrying slow polymorphisms results in the production of enzymes with diminished metabolic activity. The frequency of the NAT-2 slow polymorphisms in the general population is about 30%, and its presence increases the risk for bladder cancer after exposure to certain toxic chemicals, but appears not to increase the risk for the disease without the exposure (Katoh et al., 2000). Similarly, carrying a particular genetic variant of the MAOA gene does not appear in and of itself to increase the risk for antisocial behavior. But the exposure of carriers of this variant to mistreatment as children substantially increases their chances of antisociality (Caspi et al., 2002).
These and other data linking genetic risk factors and their phenotypic expressions provide a convincing dismissal of the view of genetics as destiny. But real appreciation of the probabilistic nature of genetic influences arises when one realizes how frequent common risk variants are and that, most likely, we all carry risk variants for something! So, what is rare and what is common?
Rare and Common Genetic Variants
What is referred to as a rare genetic disorder is a condition typically caused by a single genetic factor such as chromosomal abnormality or a deleterious mutation. One example is 18p syndrome, in which a congenital deletion of a portion of chromosome 18 leads to a variety of severe health symptoms, malformations, and mental retardation; currently there are 150 cases reported in the literature (Wester, Bondeson, Edeby, & Anneren, 2006). Illustrations of different genetic mechanisms that lead to the manifestation of rare and debilitating conditions are single deleterious mutations. Examples of this mechanism are severe hydroxylase deficiencies, inborn conditions caused by genetic alterations in the CYP11B gene on chromosome 8, which are characterized by dehydration, occasional vomiting, poor feeding, failure to gain weight, and intermittent fever (White & Rainey, 2005). These deficiencies are seen in fewer than 200,000 individuals in the United States (i.e., less than .001% of the population). Then there is a large group of uncommon genetic conditions of both chromosomal and genetic origin (e.g., Down syndrome and PKU) whose incidences are lower than .01% in the general population. For example, the incidence of Downs in American newborns is 1 in 600 to 1 in 800; the incidence of abnormalities increases dramatically with womens age at childbirth (http://www.nichd.nih.gov/publications/pubs/downsyndrome/down.htm). The incidence of PKU is 1 in 15,000, with a wide range in different populations. Collectively, although rare, these conditions constitute a substantial number of pediatric illnesses and thus create a fairly large group of children eligible for special educational services (Rimoin, Connor, Pyeritz, Korf, & Emery, 2001). As noted earlier, these rare and severe conditions are typically marked by higher penetrance.
Yet, the real grand entry of genomics into all areas of medicine, and gradually into education, is associated with common conditions, that is, those observed in 1% to 50% of the population (Guttmacher, Jenkins, & Uhlmann, 2001). Studies of human diseases and disorders have historically been driven primarily by the cultural values of humanity, where first priority was given to the sick and needy; lately, however, more and more inquiries are aimed at understanding normal human variation. This interest in normal variation is enhanced by mounting evidence that many human conditions, especially common diseases such as diabetes, hypertension, cancer, heart disease, psychiatric illnesses, and developmental and learning disabilities, are rooted in normal variation. They are multifactorial in nature, arising from the interplay between genes and environments. They are also polygenetic, that is, influenced by many genes. The incidence of common conditions is influenced by lifestyle and risky or protective environments. Moreover, the multifactorial nature of these common conditions makes them virtually indistinguishable from the extremes of traits in the general population.
Common conditions arise as context-dependent processes that result from a variety of interactions over time and environments. Dependence on context assumes that there is no one-to-one correspondence between any single causal factor (either genes or environments) and the condition: The same genotype can express itself differently in different environments and the same environment can influence different genotypes in distinct ways (Plomin, DeFries, McClearn, & McGuffin, 2003).
It is the study of common conditions that distinguishes genomics from genetics. Guttmacher and Collins (Guttmacher & Collins, 2002) defined genetics as the study of single genes and their effects and genomics as the study of multiple genes and their interactions in the genome. In fact, this distinction marks the transition from a treatment of a single gene disorder with high penetrance to developing predictive, preventive, and personalized (Weston & Hood, 2004) approaches to medical and educational practices for dealing with common conditions.
Heritability of Traits Related to Schooling
To understand the interactionist nature of human development, it is important to consider first the main effects of both genes and environments. In this context, the statistic of heritability is of considerable help.
The concept of heritability is central to the field of genetics and to the study of heredity. The heritability statistic was initially developed by Ronald Fisher at the beginning of the twentieth century and since has been commonly used as a first estimation for the importance of genetic influences on individual differences in a trait. The heritability statistic has a number of pros and cons that have been discussed in detail in the literature (Sternberg & Grigorenko, 1999). In the context of this essay, however, what is important is that studies of heritability show the presence of genetic influences on virtually all pediatric neuropsychiatric conditions, ranging from autism to learning disabilities. What is even more striking is that pretty much any psychological process, skill, or indicator related to learning or schooling (e.g., indicators of numeracy, literacy, or general cognitive competence) shows a non-negligible influence of genetic factors on its development and/or acquisition (Walker, Petrill, Spinath, & Plomin, 2004).
The tricky part is translating this general appreciation for the importance of genetic influences into concrete genes, describing specific magnitudes of these influences, and elucidating pathways linking genes, the brain, and behaviors. It is at this juncture where data from genomics studies need to be carefully linked with findings from psychology and education. Progress in understanding this link has been slow in coming. What we know for now suggests that traits related to typical and atypical learning in the general population (excluding those rare severe cases mentioned earlier) appear to be controlled by multiple genes of small effect (Savitz, Solms, & Ramesar, 2006). In other words, it likely takes several genes to form the genetic foundation (Grigorenko, 2004) for an emergent skill of, for example, phonemic awarenessthe awareness of the sounds (phonemes) that make up spoken words. This skill forms the foundation for literacy. In addition, as in the earlier example of the PAH gene, in which many deleterious variants result in the development of PKU, many alternative variants of the same gene can contribute to the manifestation of the same phenotype; this phenomenon is known as genetic heterogeneity. When many different things contribute to a single outcome, there inevitably is variation in the outcome. Thus, we see quite a range of individual differences in phonemic awareness, whose heritability is estimated at around .7 (i.e., 70% of the variance capturing individual differences in phonemic awareness is attributable to individual differences in genes), based on the fact that many different genes contribute to a single outcome. (As an analogy, consider a house constructed by many different buildersthe room for error and creative divergence from the plan is much larger than for a single builder.) But the mere assembly of genes is not the only issue to consider. Different polymorphisms in these genes will express themselves differently in different educational settings, adding more variability to how the outcome (phonemic awareness) will turn out. And, to add even more complexity to the discussion, consider the following. The same genetic factors can have both risk and protective functions. For example, people who carry the NAT-2 slow polymorphisms (mentioned earlier) have an increased risk of bladder cancer but a decreased risk of colon cancer (Vineis & McMichael, 1996). Similarly, hypothetically, a genetic variant that puts an individual at risk for social disabilities might be an enhancement variant in the development of creativity or some other psychological trait.
Thus, the sum total of an individuals genes and lifetime environmental exposures (for example, classroom experiences) determines whether a particular developmental condition is manifested as a diagnosable category. As discussed earlier, it appears that many genetic variants relevant to educational attainments are both heterogeneous and common in the population, which helps explain the high prevalence of many developmental disorders such as ADHD and learning disabilities (LD), and simultaneously explains why these variants are difficult to pinpoint. The working hypothesis is that many people have the risk variants but do not develop a fully manifested disorder (e.g., ADHD) because they lack the other genetic or environmental components or triggers needed to develop the condition, or, conversely, carry protective genetic variants or experience beneficial environments that prevent them from the realization of the disorder. Of interest is the current elevation of rates for LD and ADHD even from 10 years ago, which has been noted both by front-line educators and researchers (Fletcher, Lyon, Fuchs, & Barnes, 2007)]. There are, of course, multiple reasons for such an elevation, including changes in policies, diagnoses, and other factors. Yet, another possibility relevant to this essay is the consideration that the modern environment in general and the schooling environment in particular might act as triggers for hidden genetic risk factors. Although these factors were present in previous generations of children, risky environmental triggers (e.g., diets high in saturated fats) might have not been as prevalent as they are now. Thus, perhaps identifying both genetic and environmental risk factors and preventing them from interacting will reduce the elevated frequencies of these and other developmental conditions.
I began with a comment on the possible importance for educators of considering recent developments in the field of genomics. To prepare the ground for this argument, I briefly discussed several concepts from genetics and genomics. This discussion may have brought the reader to a number of understandings. Specifically,
Genetic influences do not determine specific phenotypic outcomes; in the overwhelming majority of cases, they predispose for a number of phenotypes, each of which might or might not manifest in particular environments.
Even most deterministic genetic variants have a statistic of penetrance associated with them, indicating that when a predisposition is inherited, it often requires specific triggers in the environment to result in the manifestation of this predisposition.
Specific genetic influences tend to be strong for the rare severe conditions and are milder and probabilistic for common traits and conditions.
Common conditions appear to be influenced by many genes acting in conjunction with many environments; yet, these common conditions are characterized by substantial heritability coefficients and call for the use of methodologies associated with genomics, the study of the whole genome rather than single isolated genes.
Most (if not all) traits and skills associated with learning and school achievement tested so far also demonstrate substantial heritability, indicating the importance of genetic influences for their manifestations; these influences, however, are emergent and attributable to the effects of many genes working together in contextual settings. These realizations are important both for understanding the role of genetic factors in human development and for forward-thinking ideas of bridging genomics and education.
What Can Educators Learn from Medical Practitioners?
Although genomic science has been slow to enter the consciousness of practitioners in educational circles, it has had a substantial influence in medicine, public health, and public consciousness (Epstein, 2005, 2006). One indicator of this influence is that biotechnology companies are beginning to market genetic tests directly to the public (Jacobellis et al., 2003). As more data link the human genome and human conditions and behaviors, scientists face a very important challenge of the genomics erathe translation of genomic knowledge into public benefits. In medicine, this challenge is specifically apparent in the context of preventing and treating common conditionssuch as hypertension, diabetes, and cardiovascular disordersso that individuals at genetic risk for these heritable conditions may benefit from various forms of health prevention and intervention (Khoury, 2003; Khoury, Burke, & Thomson, 2000). These prevention measures and interventions are thought to include pharmacological prevention and treatment options, behavioral modifications conditioned on genetic risk, and surveillance and lifestyle monitoring.
Many frameworks have been developed to bridge genomics and medicine. Here I briefly discuss only one of them, developed by the Centers for Disease Control (Kardia & Wang, 2005). In this framework, the translational process unfolds within two intersecting bidirectional continua, one of which reflects the relationship between research and practice, and the other, the targeted recipient of the servicesan individual, in the case of clinical medicine, and a society, in the case of public health. The four resulting quadrants organize the interface between science and practice by linking
individualized medicine and scientific research through risk communication, informed consent, formulation of health-based decisions, and enhancement of providers’ knowledge of research;
individualized medicine and practice through patients’ genetic education and counseling, behavior modification and patient adherence, medical decisions, and applied training of providers;
population health and research through enhancement of the genetic literacy of the general public, forming and studying public responses to direct-to-consumer marketing, assessment of genetic service needs, and forming patterns and investigating family dynamics and communication in the face of the presence and transmission of genetic risk; and
population health and practice through mass media approaches to health education, public health advocacy, increased awareness of family history as a tool for public health prevention, and development and installation of social support interventions.
This framework has been rapidly developed with the intention of penetrating major public and private networks of health providers. At the end of 2005, some 500 genetic tests were publicly available, and more tests are being planned, tested, and commercialized every day. In this atmosphere, it is crucial to ensure that this knowledge and these techniques are used to improve peoples lives. Of special importance are applications of these newly developed approaches to children. The twentieth century is full of illustrations that society influences technology as much as technology influences society. It is the responsibility of researchers and practitioners to actively participate in the incorporation of new technologies into public life. Given the discussion earlier about the established role of heredity in development at large and in learning and schooling in particular, it is especially important that psychologists and educators participate in this process.
The current explosion of genomics is one of the most challenging scientific revolutions in terms of understanding humankind and individuality and in considering the various possible social implications of this understanding. Given current events in medicine and correspondingly in pediatric and developmental sciences, it is important for educators to participate in the genomics era and to speak knowledgeably and authoritatively about the needs of children and the interface of these needs with genomics and education.
It is also essential to note the importance of the bidirectionality of this participation. There is a view that stunning scientific and technological advances in genetics and genomics only matter when they benefit people (Guttmacher et al., 2001). The crucial contribution that educators can make in understanding the genetic bases of both disabilities and abilities is in providing information on how abilities and disabilities, whether in reading, math, or another academic domain, manifest themselves in classrooms and to what extent they are modifiable and with what educational techniques.
As at the beginning of the last century, when the introduction of abilities testing resulted in understanding sources of individual differences between students in classrooms and the rise of new professions such as school psychologist, the introduction of genetic testing into the everyday lives of children will further our understanding of why children differ in the classroom and also will lead to the appearance of new career trajectories in education. It is also possible that many people will lament genetic testing as they lamented ability testing.
So, why might educators get involved in the translations of findings from genomics? I see at least three reasons. First, as I pointed out earlier, educators have intimate knowledge of how individual differences among children manifest themselves in the classroom. Thus, their input is crucial in understanding relevant phenotypes, or observable characteristics, for capturing these individual differences and explaining their sources, whether genetic or environmental. In fact, the participation of educators in the translation of genomics will not only benefit education, it will also benefit genomics. For example, current work on the genetics of individual differences in reading (Grigorenko, 2004, 2005) is driven by a model of reading as a complex componential skill that arose at the junction of education and psychology (Snowling & Hulme, 2007). This model dissects reading into lower-level trainable skills (e.g., phonological processing, word decoding, and vocabulary acquisition). In fact, it appears that it is these lower-level processes that are influenced by genes (Grigorenko, 2005). The identification of genetic vulnerabilities for the emergence of these individual differences in lower-level processes might inform both the identification of children at risk for reading failure and prevention of this failure (Fletcher et al., 2007). Thus, educators and psychologists inform geneticists of what aspects of academic skills appear to be sources of individual differences in students, geneticists identify genetic bases for these differences, and the information can be used both for early identification and prevention to avoid failure using pedagogical and, possibly, pharmacological interventions.
Second, educators have always been interested in understanding the sources of individual differences among children in their classrooms. Correspondingly, new and exciting findings linking individual differences in cognition to genetic variation will no doubt be of interest to educators. For example, there is growing literature indicating that a functional polymorphism in the COMT gene is associated with a substantial amount of individual differences in cognition (Savitz et al., 2006). This polymorphism leads to the presence of one of two amino acids (valine, val, or methionine, met) in the complex protein catechol-O-methyltransferase. This protein is involved in the turnover of dopamine, one of the major neurotransmitters, in the prefrontal cortex, the area of the brain that substantiates cognitive tasks involving working memory and executive functioning (Cools & Robbins, 2004). Overall, the evidence indicates that typical individuals who are homozygous for the val allele tend to perform poorer on these cognitive tasks than do typical individuals who are homozygous for the met allele (Diamond, Briand, Fossella, & Gehlbach, 2004). This behavioral evidence is substantiated by molecular-psychiatric (Mata et al., 2006) and human brain (Zinkstok et al., 2006) neuroscience studies. Thus, overall, it appears that this polymorphism in the COMT gene may exert a genuine effect on cognition (Savitz et al., 2006). Of interest is that both alleles are approximately equifrequent, and thus are observed commonly in the general population. Yet, carrying the val allele might put a student at higher risk for academic failure; such students might need additional support in developing their working memory, planning, and other aspects of metacognition. However, it is important to remember that these common polymorphisms are responsible for only a small portion of individual differences on cognitive tasks. Other genes influence cognition and are important to consider. Thus, in the same way genetic profiling might lead to individualized medicine, it might also lead to individualized education.
Third, in many instances, at least in those related to policy issues in special education, parents have triggered and promoted major changes in the educational system in the United States. When parents, informed by genetic findings, come to educators asking for advice and accommodations for their children, educators will be expected to be ready to respond. Informed responses are based on knowledge and accurate interpretation of scientific findings. For example, another gene relevant to cognition is BDNF (Savitz et al., 2006), which codes for production of a protein that helps to support the survival of existing neurons and participates in the growth and differentiation of new neurons and synapses (Pang & Lu, 2004). This gene also has a common polymorphism that has been associated with cognitive functioning, in particular memory (Egan et al., 2003). Does this mean that a student who carries the undesirable version of this polymorphism (the met version) is destined for academic failure? Not at all! Yet, that student might need more scaffolding, more time on task, and more support in class. And, because quite a few commercial companies appear to be gearing up to offer genetic profiling of cognition, educators might need to be ready to deal with parents who will purchase profiles that address genes for learning and bring them to school. Consulting with parents and teachers on individualized educational approaches (again, whether in a classroom, smaller group, or one-on-one) for students based on their genetic profiles might be a task for an educogenomicist.
So, overall, how might the participation of educators in the explanation, incorporation, and dissemination of genomics and genetic knowledge look if it were to occur in the future?
How the Merger between Genomics and Education Might Work
The main point of introducing genomics into the field of education is to find ways to capitalize on genetic information. The incorporation of genomics knowledge will be particularly relevant to special education, especially for finding the best possible pedagogical interventions for children with special needs and reducing the burden that developmental disorders place on society. In other words, the fields steady progress in understanding genetic etiologies of atypical development (for a review, see Rutter, 2006) will result in the development of more effective interventions. Most likely, these interventions will combine pharmacological and behavioral approaches, initially for special education and possibly later for general education.
Along with expanding our knowledge of genomics, research is extending our knowledge of normal variation. Intriguingly, as mentioned earlier, behavioral indicators of learning-related processes appear to be under substantial genetic influence (Plomin, 2005). Correspondingly, it is conceivable that rather soon we will understand, at least partially, some of the genetic bases of memory, language, reading, mathematics, and writing (Fisher & Francks, 2006). Identifying genetic pathways involved in the development of these psychological processes will most likely lead to experimental manipulations with these pathways and the identification of pharmacological and environmental interventions capable of enhancing them. These developments will no doubt create a variety of new challenges for educators, ranging from parental demands for specific individualized educational approaches for their children based on their pattern of genetic variants to the introduction of tests for pharmacological enhancers prior to examinations or achievement testing similar to those administered in sports for steroids. So, how can we prepare for these new challenges?
First and foremost, the education field can examine and learn from the field of public health. The World Health Organization, the CDC, and the National Institutes of Health have launched major initiatives aimed at designing and redesigning major approaches to public health. Launching comparable initiatives for schooling (e.g., discussing the crossroads between genetic testing and education) in the United States might be an important step toward building the bridge between the two domains. Another key move might be adapting or redesigning the medical framework discussed earlier to fit the needs of education. The field of education does not have to borrow from medicine in its attempts to incorporate genomics into schooling, but it might consider observing what is going on there and developing corresponding translational models for the American educational system.
Second, partnership models should be developed so that pediatricians and primary care physicians can work with mental health providers and educators and have access to regional teams of professionals equipped with the necessary expertise in behavioral medicine, genetic counseling, and genomics. There is evidence in the literature suggesting that such collaborations are currently lacking and that more needs to be done to ensure delivery of appropriate services to children with special needs (Sneed, May, & Stencel, 2004). This team-based approach to an individual child, especially to a child who has difficulties in school and might have a variety of associated somatic and mental health issues, is crucial. These teams of professionals should have access to real-time databases that merge online a childs education records and HIPAA (the Health Insurance Portability and Accountability Act)-protected information generated by all practitioners working with a child. The availability and use of this information should lead to improved individual learning outcomes and maximization of learning potential for every child. Initial models for such an exchange of information among medical clinicians, schools, parents, and other care professionals are being developed (e.g., by Raging Knowledge Educational Service of Westport, CT). Of course, it is critical to consider the various ethical implications of bringing genetic data to school and possible misuses of these data. I hope this essay will trigger a debate regarding the relevant issues, which will hopefully receive much attention at national and international policy levels, as well as in academic circles.
The National Institutes of Health Task Force on Genetic Testing and the Department of Health and Human Services Secretary Advisory Committee on Genetic Testing are two government bodies engaged in the development of relevant recommendations. It might be productive for the U.S. Department of Education to join these discussions. Although none of these recommendations have yet been implemented, this is a crucial moment at which such recommendations are being formed (Javitt, Stanley, & Hudson, 2004; Stolberg, 2007), and educators might want to be a part of the discussion. Of note here are the results of surveys indicating that, in general, the general public is optimistic about and supportive of the potential benefits of genetic testing, assuming that such knowledge can result in control over the development of health impairments based on genetic susceptibilities (Shaw & Bassi, 2001). If the public sees the benefits of genetic testing, it will embrace it and bring its results to the classroom, the environment in which children spend the overwhelming majority of their time and where their genetic risk factors interact with environments the most.
Third, with further development of applied technologies, it might be possible to develop elements of preventive developmental and educational genomics. Because, broadly speaking, genetic information as captured in DNA polymorphisms does not change across the lifespan, genotyping young children for crucial genetic variants associated with developmental disabilities (assuming they are identified reliably and validly!) might be important. In this context, the following steps might be considered: (1) predict who is at risk for developmental disabilities and comorbid conditions; (2) identify and intervene to prevent the behavioral manifestation of developmental disabilities in persons at risk; (3) identify persons in an early stage of developmental disability and intervene and remediate to prevent later complications; and (4) individualize complex treatment and remediation approaches to improve outcomes. Globally speaking, these prevention and early-identification techniques will be aimed at minimizing the trial-and-error approach and maximizing individual differentiation. If bringing a gene chip, with its exhaustive information about genetic polymorphisms, to a doctor to optimize diet, vitamin supplementation, or medication no longer sounds like such a futuristic idea and, in fact, is expected to be in place in the near future (Epstein, 2006), why cant we start thinking about the possibility of using individualized genetic information to help children in school settings? It is possible that such anticipatory guidance, based on genetic information, will not only result in more effective pedagogical approaches and beneficial outcomes, but will also empower the system to avoid manifestation of various developmental disorders (e.g., learning disabilities).
Fourth, it is very important to consider educating educators on relevant issues. Most practicing educators have had little if any training in genetics and genomics. Plomin and Walker (2003), for example, reported the results of a review of major educational psychology textbooks. They found that these textbooks either did not include any material on genetics, mentioned genetics only while talking about specific developmental or learning disorders (e.g., ADHD), or included a maximum of three pages on genetics. Although there is no comparable study for the textbooks in psychology and child development, a superficial investigation of such textbooks suggests that, although often mentioned, genetics and genomics get a limited number of pages in these textbooks. To illustrate, of the 10 textbooks on child development published between 2000 and 2006 and examined for this article, the total number of pages devoted to genetics and genomics was ~.13%.
Recent advances in the field and an explosion of scientific and popular reports on genes account for this and make it very difficult to keep up. However, educators have always been the first point of reference for concerned parents. If children are having learning difficulties, it is important for their teachers to know what kinds of referrals to make and to whom they should be made. Of special value here is working with the childs family, both in terms of making inquiries into family history and designing family-based prevention. Thus, to be ready to embrace the genomics era in schools, educators will need to be informed about the role of genomics in education. If we expect that genomics research will result in improved health benefits, why should we not consider learning benefits from the incorporation of this research into education?
As stated earlier, there is no expectation that front-line classroom teachers will become experts in genetics and genomics. Rather, they will provide an increased awareness of the relevance of genomics findings to both development and education and their use as a further source of guidance in maximizing educational outcomes for all students. This awareness must be accompanied by the realization that access to information should be moderated by an educogenomicist. Such an expert can interpret, in an informed, professional, and ethical manner, the genetic and educational information available on an individual child and advise both family and teachers on how to maximize schooling and learning environments for that particular child and any siblings that might be at genetic risk for the condition this child has.
This brings us back to Abby. What possible sequence of events might help Abby break the cycle of academic failure? Suppose, based on her behavioral manifestations, Abbys parents reply to an advertisement for a particular genetic test and then test Abby for genetic variants that lead to a predisposition for language disabilities. As a result of this test, her parents are told that Abby carries one or more genetic risk factors for the development of language disability. These results are then brought back to Abbys school; based on these findings, her parents suggest that Abby may be eligible for special services and an Individualized Education Program (IEP). It seems imperative that when genetic data enter educational decision making, an expert with corresponding skills (an educogenomicist) be a part of the IEP team. Clearly, there are many important issues to consider here, such as whether educogenomicists should be placed in the public or private sector, where the funds for the support of these activities should come from, how the corresponding issues of social justice and fairness should be addressed, whether discrimination of any kind can be associated with the use of genetic information and how it can be prevented, and whether the children themselves should participate in decision making with regard to the use of genetic information in their education. An educogenomicist would be expected to be in touch with Abbys healthcare provider, consider recommending pharmacological agents (yet to be discovered) relevant to overcoming language disability, review Abbys family history, request subsequent genetic tests, if needed, and, most importantly, be able to identify and recommend best educational practices for Abby and prevention practices for her younger siblings, who may be at genetic risk for language disabilities and who might not yet even have entered the educational system. Having collected all this information, the educogenomicist would be able to make proper recommendations for Abbys IEP and her teachers and provide proper consultations for Abbys family and her siblings. This is only one of many possible models of how genomics discoveries might be incorporated into everyday school life.
Yet, no matter how optimistic some of these possibilities sound, it is well known that the genomics era has brought with it many concerns and ethical dilemmas. Here I name only a few. First, as is true for any type of testing, the initiation of genetic testing without a full understanding of the effects of the prevention or intervention that should follow the testing is ill advised. For example, recent reports of genes related to the manifestation of reading disabilities resulted in a flurry of statements by the mass media about corresponding genetic testing. It is important to understand that although these discoveries are very promising and encouraging, they are far from accepted as replicated findings among scientists and very far from being turned into commercial genetic tests. Besides, given issues of penetrance and the impact of environment on manifestation of genetic risk factors, these genetics tests are meaningful only in conjunction with prescribed pedagogies and other relevant interventions.
Nevertheless, from the point of view of public perception, exemplified multiple times in the mass media, testing is the direction in which practices are going, at least with regard to the emerging reality of genomic medicine (Epstein, 2006). In this context, it seems crucial to reiterate cautionary points made by a number of scientists and popularizers of science. Evaluation of the predictive power of genetic risks, especially for common conditions, is meaningful and substantial only in the context of considering many genes and environments (e.g., lifestyle, diet, and pedagogical strategies) simultaneously. And even then the predictive power will not be absolute and will remain probabilistic, or based on likelihoods of specific outcomes. As Epstein (2006, p. 436) stated: That risk assessment or profiling can be done does not mean that it actually will, or, indeed, should be done. Decisions about testing should be made by informed professionals (e.g., educogenomicists) in the context of a child or familys needs, the predictive power of specific tests with regard to the improvement of educational practices, privacy protection, parental permissions and student consent, and compliance of the educational system in delivering the needed pedagogical strategy; a full discussion of these issues is beyond the scope of this article. And, a special issue of importance is student assent/consent; this is an unexplored area of educational ethics that needs to be examined. All these issues are new to educators and deserve careful investigation and open discussion. And the time for these considerations and discussions is now, before parents start approaching the school system with results of genetic profiling asking for feedback and changes in educational accommodations for their children.
A second concern is the challenge of molding research findings into practice. This warning, of course, is relevant to any educational intervention, with or without a link to genomics. The field has to think deeply about establishing criteria for evidence of any intervention prior to disseminating this intervention into practice. Yet, with medical genetics and genomics changing its identification from largely research-oriented science to a service-oriented specialty, as noted in Arno Motulskys 1977 presidential address to the American Society of Human Genetics, we can only ask when these services will enter education through its connection with healthcare. Because genetic research advances into the field of academic abilities are producing many new and exciting findings (Fisher & Francks, 2006; Grigorenko, 2005), it is only a matter of time until these findings are translated into applications and become a new facet of American education. The challenge is to be prepared for this entrance with relevant knowledge and having had important discussions about the associated financial and ethical issues.
Third, it is particularly important to understand the roles different educators, teachers, administrators, and educogenomicists might play in generating and interpreting the results of such profiling. The discussion earlier touched on the importance of raising awareness among educators in general and classroom teachers in particular with regard to knowledge of genetics and genomics. Although raising awareness is necessary, it is also important to realize the expert boundaries with regard to knowledge of genetics and genomics. Similar to interpreting results of psychological or psychoeducational testing, the interpretation of genetic testing, especially at the junction of this testing and pedagogical practices, should be done by specially trainedand probably licensedprofessionals. With the era of genomic medicine approaching and the beginning of the infusion of genomics into education, I believe that new models incorporating this knowledge and establishing bridges between genomic medicine and education are required. This is why this essay stresses the importance of starting relevant discussions as soon as possible.
Fourth, given the discussion at the beginning of this essay, it is very important to be mindful of the complex interactions of the genetic script with social variables such as socioeconomic status, ethnicity, and culture. The human genome is not culture free or fair; it has deep marks of human evolution, history, and geographic migrations, and all these considerations must be taken into account. There is no doubt that the integration of genomics into education will result in even more heated discussions of gender and ethnic differences in achievement and their etiologies.
Finally, especially in light of the current fascination with accomplishments of genome-related research, it is crucial to avoid excessively reductionist strategies and to stay as far as possible from the geneticization of humanity. Some may remember the 1997 movie Gattaca, which presented a retrofuturistic interpretation of a eugenic society where genetic engineering and in-vitro fertilization were used to generate children of predetermined gender, intelligence, life expectancy, physical characteristics, and health. This movie generated several discussions among specialists and laypeople and raised many important questions that are still unresolved now, almost 10 years later. The movie showed in a convincing way why deterministic interpretations of genes do not and cannot work.
Although reductionism is important in trying to elicit specific mechanisms contributing to complex dynamic processes such as human development and schooling, it is vitally important not to regress to what Dennett has called greedy reductionism: In their zeal to explain too much, too fast, scientists and philosophers often underestimate the complexity, trying to skip whole layers or levels of theory in their rush to fasten everything securely to the foundation (Dennett, 1995). Let us refrain from overzealousness!
A balance of research-based evidence for benefits and drawbacks and unquestionable, fundamental consideration of individuals rights should guide decisions about the introduction of individualized genomics into education. None of these considerations are ethically neutral and, therefore, should all be considered with great care. Nobody says this will be easy. We all remember and must never forget the sad history of eugenics and its impact on society; many are worried that the general public might see some parallels between that history and the modern achievements of genomics (Stehney, 2004). Thus, we should proceed with caution, but we shouldwe mustproceed.
This work received partial support from a grant under the Javits Act Program (Grant No. R206R00001) administered by the Institute for Educational Sciences, U.S. Department of Education, and from a grant R21 TW006764-02 administered by the U.S. National Institutes of Health.
I express my gratitude to Dr. Robert J. Sternberg for encouraging me to write this essay, to my colleagues at the PACE Center at Yale/Tufts and EGLab at Yale for providing valuable feedback on this manuscript, and to Ms. Robyn Rissman for her editorial assistance. I am particularly thankful to Ms. Delci Lev, a practicing school teacher, for reading the essay and commenting on it from the frontlines of education. I am also grateful to the reviewers whose comments on the manuscript were of great help in revising it.
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