Genetic patterns not only predispose people to wellness or health, they are also predictive of social success or failure. Although the link between genes and life outcomes is weak, it is supported by an analysis of data that had been collected from almost 1000 individuals over four decades. Also, the link remained even when the analysis accounted for social-class origins. That is, the analysis distinguished between the advantages of being “born on third base” and the advantages of being born with a favorable polygenic score.
The link was reported by scientists based at Duke University School of Medicine, who caution that it is only weakly predictive. For example, the link cannot, on the basis of currently available data, guide educational interventions. Personalized education, unlike personalized medicine, remains a distant possibility.
“We can make only very weak predictions about how far a child can go in life based on their genes,” said Daniel W. Belsky, Ph.D., a Duke University researcher who works at the intersection of genetics, the social and behavioral sciences, and public health. At Duke, Dr. Belsky and colleagues completed a new study that extended the results of an earlier study that had been undertaken by the Social Science Genetic Association Consortium. In the earlier study, a genome-wide association study, millions of genetic variants in more than 100,000 people were examined. And it was found that these variants could be aggregated and turned into a polygenic score that was linked with educational attainment.
Dr. Belsky and colleagues reconsidered the old data in the light of new data from the Dunedin Study, an ongoing investigation of life outcomes that is following almost 1000 people in New Zealand from their birth though their fourth decade. Over the course of the Dunedin Study, participants have completed assessments evaluating their developmental milestones in childhood; their traits, behaviors, and aspirations through adolescence; and their attainments and outcomes in adulthood.
Dr. Belsky and colleagues matched the genotypes of Dunedin Study participants with the genome-wide associations with educational attainment that had been reported previously. The results revealed that genetic links with educational attainment predict outcomes that go well beyond the completion of schooling, as Dr. Belsky and colleagues hypothesized.
Details of the Duke study appeared June 1 in the journal Psychological Science, in an article entitled, “The Genetics of Success: How Single-Nucleotide Polymorphisms Associated With Educational Attainment Relate to Life-Course Development.” The study reported five main findings.
- Polygenic scores predicted adult economic outcomes, even after accounting for educational attainments.
- Genes and environments were correlated: Children with higher polygenic scores were born into better-off homes.
- Children’s polygenic scores predicted their adult outcomes even when analyses accounted for their social-class origins; social-mobility analysis showed that children with higher polygenic scores were more upwardly mobile than children with lower scores.
- Polygenic scores predicted behavior across the life course, from early acquisition of speech and reading skills through geographic mobility and mate choice and on to financial planning for retirement.
- Polygenic-score associations were mediated by psychological characteristics, including intelligence, self-control, and interpersonal skill.
Together, the findings provide glimpses into how genes may ultimately shape our lives over time, but the researchers emphasize that the associations between polygenic score and life outcomes are small. Also, the polygenic scores did not predict important life outcomes, such as physical health. Finally, the data currently available do not provide sufficient information to guide educational interventions or other real-world applications.
Nonetheless, the current study raises provocative questions that could stimulate discussion among scientists, policymakers, and the members of the public. “'Precision education' or other tailoring of environments to children's genomes is not possible with the data we have in hand today, but our findings suggest that such data may someday become available,” Dr. Belsky noted. “It is vital to have the conversation about what that might mean and how we will deal with it before it happens.”