Alicia Garcia-Sierra, a sociologist at the Universidad Carlos III in Madrid and a former member of the LIVES Centre | César Fuster Llamazares
What if the weight of our DNA in the course of our lives depended on public policy? A study published in April 2026 in the American Journal of Sociology compares people born just before and just after the cutoff set by the Education Act of 1944 in England. The finding: once school fees were abolished, two people with different genetic predispositions saw their trajectories — education, income, wealth — move markedly closer together. An interview with Alicia Garcia-Sierra, a sociologist at the Universidad Carlos III de Madrid and a former member of the LIVES Centre.
Why did you choose the 1944 English education reform as your area of investigation rather than another context?
We chose it because it offered an unusually clean natural experiment. The reform's effect was tied directly to a person's year of birth: those born in 1934 or later were covered by the new law, those born just before were not. That sharp, essentially arbitrary cutoff lets us compare people who are otherwise very similar and isolate the effect of the policy itself, rather than other social changes happening over the same period.
Your study focuses on the 1944 Education Act. Why is it important to understand how a post-war education reform influenced the link between DNA and social success today?
Because it tells us whether the effect of something we usually treat as fixed (genes) is actually shaped by policy. If a single reform can change how much your DNA predicts your future education, income, and wealth, that matters both scientifically and politically. Scientifically, it pushes back on the idea that genes set a ceiling regardless of environment. Politically, it means how much "nature" determines someone's life chances is partly a policy choice.
For the average person, the idea that our genes might predict our future level of education or bank balance can be bewildering. You measure genetic influence using a polygenic score for educational attainment. Could you explain this to us?
In this context, we have to think of it as a DNA score. Large genetic studies have identified thousands of tiny variations across the genome, each associated with a very small change in how many years of education someone tends to complete. On its own, none of these variations matters much. A polygenic score adds all of those tiny effects together into a single number summarizing someone's overall genetic predisposition toward more or less schooling.
So this is a statistical tendency, not a destiny?
Yes. It explains part of the variation between people, not the whole story (for instance, plenty of people with a low score still study for many years, and viceversa). What we used it for specifically was to ask a follow-up question: does that predisposition end up mattering more, or less, depending on the environment someone grows up in?
Your research found that the reform reduced the association between genes and individual success by between a fifth and a third of a standard deviation. What does this mean in practical terms for the individuals concerned?
Before 1944, if you compared two people with different genetic predispositions for education, the gap between them in how far they went in school, how much they earned, and how much they accumulated over their lives was substantially wider. After the reform, that same genetic difference translated into a noticeably smaller gap in real-life outcomes.
You argue that this reduction in genetic influence is evidence of greater 'equality of opportunity'. Why, in your view, is a society in which genes are less predictive of future outcomes a fairer society?
Because nobody chooses their genes, just as nobody chooses the family they're born into. From a luck-egalitarian view, inequalities that stem from things entirely outside a person's control (such as their genes or their family origin) are the least defensible kind of inequality, more so than inequalities that come from differences in effort or choices people actually make. So a society where genes predict less of your future is one where more of your outcome is left open to what you actually choose, rather than being largely pre-written by your DNA at birth.
The study shows that the reform has mainly benefited people with lower genetic potential. Can we say that the expansion of education serves primarily as a 'safety net' for those who would struggle the most without it?
Before the reform, students with a higher genetic predisposition for education were already staying in school under the old, selective, fee-paying system. So the people that the reform actually moved were those who, without it, would likely have left school early: often precisely the ones with a lower genetic predisposition.
So, the reform behaved less like a boost for the already-advantaged and more like a floor: it caught the people who would have struggled most to stay in school on their own. I'd be careful about over-extending the metaphor, since the policy wasn't designed as a targeted safety net, it was universal. But in terms of its actual effect on outcomes, it did land disproportionately on those who needed it most.
One of the more surprising findings of your research is that, while the influence of genes has declined, that of parents' social background has remained very stable. Why has schooling managed to counteract the ‘genetic lottery’ but not the ‘family background’ factor entirely?
Because school fees were only ever part of what family background buys you. The reform removed one specific, concrete barrier — the cost of staying in secondary school — and that was enough to change how much genetic predisposition mattered. But wealthier, more educated families pass on advantages through many other channels that a fee-abolition law simply doesn't touch: expectations, social networks, help navigating the system, access to the better — often selective — schools, extracurricular opportunities. A single policy like the one we study can't neutralize all the other ways family background shapes a child's trajectory. That is consistent with what the historian Peter Mandler has argued about that period in the UK: education expanded access, but it didn't equalize opportunity by social class.
What practical lessons should today's policymakers draw from this study when designing educational reforms?
First, policy can genuinely change whose outcomes are shaped by what — not just how many people get more education, but which factors end up mattering for who ends up where. Some things are beyond a person's control: their genes, their social origin. If a reform reduces how strongly these predict their future, that is a real gain in equality of opportunity.
Second, not all reforms do this. Other research on policies that changed academic tracking, rather than removing cost barriers, found different results: genes mattered more afterward, not less. So, there's no single formula: policymakers today should be precise about which specific barrier they're removing — cost, tracking, geographic access — because different barriers interact differently with genetic and social inequality.
You spent several years at the University of Lausanne and were also a member of the LIVES Centre. What did you gain from those years? What did the Centre offer you?
Those years were, by far, the most intense learning experience of my academic career so far. Working alongside a team of exceptional researchers like the EQUALOPP team helped me take the leap from PhD student to assistant professor. On a personal level, I also loved my time there. LIVES has a fantastic environment and genuinely great people, and that made all the difference.
Interview by Kalina Anguelova
Garcia-Sierra, A. & Grätz, M., (2026). Does Expanding Free Secondary Education Moderate the Relationship Between Genes and Socioeconomic Outcomes? Evidence from the Education Act of 1944 in England. American Journal of Sociology, 131 (5). https://doi.org/10.1086/740030