In the future, should we genotype children for resilience to provide them with better, targeted interventions to help them succeed? This is the underlying thesis of an opinion piece by Dr. Jay Belsky, published last Sunday in the New York Times.
Dr. Belsky notes that much money is spent on interventions trying to help children succeed, and that the resilience of the children affects the success of these interventions. To improve intervention success, he suggests that genetics might play an important role, providing evidence from studies that show associations between specific gene variants and intervention success. Dr. Belsky then proposes that in the future, we should “seek to identify the most responsive children and disproportionately target them when it comes to investing scarce intervention and service dollars.” He invites us to “imagine a day when we could genotype all the children in an elementary school to ensure that those who could benefit most from help got the best teachers.” He cautions that we shouldn’t abandon children who aren’t responsive to current interventions, since they too deserve a good quality of life. In short, he argues that since genes likely make some children more responsive to interventions in our education system, we should consider targeting those children to help them succeed. Dr. Belsky rightly points out that much research is needed to better understand how relevant genes function, and stresses that this would take place in the future.
These were my main takeaways from Dr. Belsky’s article. While I see where he is coming from, his proposal gave me a sense of foreboding. Why?
Your DNA is not your destiny. Some genetic variants (alleles) are strongly predictive of certain characteristics, but most traits (especially complex behavioral traits like resilience) are not nearly so simple. Complex traits aren’t determined simply by whether you have the alleles; it’s about how they function in the individual. Many of us carry multiple genes that enhance risk for diabetes, depression, cancer, and thousands of other diseases and traits. That doesn’t mean we’ll suffer from those diseases. For example, we’ve found >60 gene regions related to type 2 diabetes, yet the effects of these genes only account for 10-15% of the risk for developing diabetes. The rest is unknown or (quite likely) environmentally based. Like diabetes, resilience is likely a very complex trait, and probably involves many different genes and regulatory regions in the genome. Each gene or region likely plays a role in the development of the trait, and while they may have measurable effects, these effects are small, especially compared to environmental and behavioral factors.
The expression of the responsible genes can be turned off and on (or modulated up and down) by environmental factors: early life exposures to lack of resources (malnutrition), toxic chemicals (like lead or mercury), and toxic behavior (like abuse). Changing the gene expression back to more ‘normal’ or ‘undamaged’ levels also appears to be possible, though research about this is in the very early stages.
Since the early life developmental period is known to be a particularly vulnerable time (as Dr. Belsky mentions), we should focus on providing support in ways that are known to help children regardless of their genetic status. Millions of children suffer from malnutrition, and are exposed to dangerous levels of toxic substances in utero or at young ages. Children live in unstable homes devoid of parental support because of poverty: parents must work multiple jobs, are in prison, or through other unfortunate circumstances are unable to spend enough time with their children. Rather than genotyping children, it makes better sense to try to address these problems first, which could help make more children more resilient in general.
Despite good intentions, using science in this way is uncomfortably reminiscent of eugenics. It also makes me think of the movie Gattaca, a movie portraying a society where one’s social rank, career, and status are based simply on their genes. It’s possible that we could accurately map the exact effects of genes on intervention effectiveness in the future. But will we understand the genome well enough to make accurate and usefully predictive judgments that can also account for environmental factors? Do we want to target kids for interventions simply based on whether they have specific gene variant that is associated with lower resilience? If we can’t account for environmental variation, then we’ll be categorizing children based on blunt genetic tools that do not and cannot account for the necessary complexity of their subjects.
Furthermore, what are some of the implications of having that information for each child? We cannot afford to provide high quality education to all of our students now. What would happen to a child who tested positive for alleles related to lack of resilience, but the school didn’t have resources to provide them help? Would their problems simply be ignored, or worse, will it affect how they’re treated and their future opportunities?
On the education side, Dr. Belsky writes that we ought to use our limited resources wisely. Is it wise to spend time and money genotyping kids to see which ones are slightly better or worse suited for interventions? Wouldn’t assessments by childhood development experts and teachers be a better way of determining this? If we’re thinking in future time where we understand genetics in the ways Dr. Belsky proposes, it wouldn’t be surprising if we understood child psychology and the relevant environmental factors far better as well. Why wouldn’t we simply just give them the tools and resources to develop plans to help them, rather than using the roundabout and limited method of genetic testing?
This opinion piece makes me think of utopian plans envisioned in the early 1900s: hygienic, neat, concrete and steel, perfect planning, and scientific answers to all of life’s problems. Life’s problems aren’t simple, and merely being able to account for a person’s genotype is one relatively small piece in a large and complex puzzle. We live in a marvelous age: we have tools available to us that allow us to measure and understand the world like never before. Still, we must be aware of the limitations of those tools, so we can avoid blundering into unintended problems that result from our own grandiose designs.
References
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Dolinoy, Dana C., Dale Huang, and Randy L. Jirtle. “Maternal nutrient supplementation counteracts bisphenol A-induced DNA hypomethylation in early development.” Proceedings of the National Academy of Sciences 104.32 (2007): 13056-13061. DOI
Rathmann W, Scheidt-Nave C, Roden M, Herder C. Type 2 Diabetes: Prevalence and Relevance of Genetic and Acquired Factors for Its Prediction.Deutsches Ärzteblatt International 2013;110(19):331-337. DOI