Genetic advantage and equality of opportunity in education

By Rita Dias Pereira

How should advances in understanding of genetic inheritance influence discussions on fairness and inequality in education? This blog discusses findings from new research which analyses the issue using data on people born in the US in the mid-20th Century.

There is an ongoing debate regarding fairness in education, with discussions on student loans, the exclusion of lower-income students and the educational divide. The underlying assumption of all these debates is that it is wrong to exclude someone from education because of their social class. But there is another factor that does not seem to be making headlines: the inequality in genetic advantage.

It is unclear whether genetic-based advantage should count as a fair or unfair source of inequality, and this article’s goal is not to defend one or the other side. But I do argue that this type of inequality exists, and that it is time we start acknowledging it so we can start discussing ways to include everyone in society, regardless of their disadvantages.

With the successful completion of Human Genome Project in 2003, scientists were able to fully unveil our genetic code. Since then, research in genetics has boomed, and today scientists are able to obtain strong and reliable genetic-based measures for several diseases and traits (think personality or cognitive ability). Those measures are what we call polygenic risk scores (or indexes) and those scores, or indexes, can now predict up to 16% of the variation in educational attainment. It is important to understand that having a high or low polygenic score does not determine your education or your cognitive ability: while it may give you an advantage or disadvantage, it is well documented that genes act through the environment – so if you have a high polygenic score for height, but don’t eat well enough in childhood, chances are you won’t be tall.

To measure fairness in education, economists often use the equality of opportunity framework. This framework does not deem inequality in educational attainment as a bad thing on its own, but rather focuses on the sources of inequality. Putting it simply, it means that if a student does not succeed in the schooling system because he or she was born in a disadvantaged family, that would be wrong. But if a student fails because he or she does not put effort into studying, then that would be acceptable. This means that the inequality can be decomposed into “fair inequality” and “unfair inequality”.

The framework of equality of opportunity typically ignores the role of genetic advantage in educational inequalities. This means that it is unclear whether genetic advantage is seen as “fair” or “unfair” inequality.

In my research I have been trying to quantify “unfair inequality,” and how it alters if we move genetic advantage from the “fair inequality share” to the “unfair inequality share”. I use data from individuals born between 1920 to 1959 in the U.S. to show that the inequality accounts for 26 % of differences in the number of years spent in education if we place genetic advantage in the “unfair inequality” category and 21% if we place genetic advantage in the “fair inequality” category.
A cohort analysis reveals that despite the spectacular increase in education for younger cohorts, there is persistent inequality of opportunity with respect to years of education and college completion.

The trend is particularly bleak if one adopts the view that genetic advantage should be placed in the “unfair inequality share”, since the educational system has increasingly been compensating genetic advantage, especially at higher levels of education. Genetic advantage goes from explaining 3.3% of the variation in college completion for those born in 1920 to 6.8% percent for those born in 1959, single-handedly increasing the inequality share from 16.4% to 19.8%.

Overall, my paper proposes a new way to look at inequality in education, one where genetic inequality is considered. The empirical results suggest that the way we treat genetic components matters for the estimates of inequality of opportunity in education, and they matter increasingly more for higher levels of education. This highlights the need to do much better in understanding the sources inequality in educational attainment, and to have a meaningful discussion about what should be counted as fair in our society.

Genetic advantage and equality of opportunity in education: Two definitions and an empirical application, by Rita Dias Pereira, is published as a preprint: bioRxiv 2021.12.14.472565

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