Sir – In recent correspondence Dr Michael O’Connell and Prof Kathleen Lynch (both UCD) outline polarised views on the role of genetic and family background factors in contributing to educational attainment. Their views both misrepresent contemporary research in behavioural genetics.
O'Connell (Letters, October 24th) suggests that children from wealthy backgrounds become highly educated largely because of the intelligence they inherit from their parents. However, we know from a meta-analysis of twin studies by Branigan and colleagues that family background (ie the environment shared by siblings) and genetic factors contribute close to equally to variability in educational attainment. Parenting, parental expectations, access to the social networks and economic resources parents have at their disposal likely matter and make a difference for educational attainment.
Prof Lynch (Letters, October 30th) makes this important point but dismisses behavioural genetics research including the work of Prof Robert Plomin, a distinguished and highly cited psychologist, as speculative and scientifically untenable.
This too is an unbalanced characterisation. Plomin has heavily publicised the role of genes for his recent book, but his most significant scientific contribution has been to highlight the role of environmental experiences not shared by siblings in explaining why people differ on a myriad of traits. His team have also provided some of the strongest insights into the role of family background in shaping educational attainment.
For instance, they have recently shown that the family environment accounts for a notable portion (36 per cent) of variation in university enrolment. In a 2017 twin study Plomin’s group showed that how children fare in education compared to their parents “. . . is influenced to a large extent by shared environmental factors . . . such as the home that children grow up in or the schools that siblings attend.”
Findings from such “genetically informative designs” provide some of the strongest scientific evidence on the importance of environmental influences and the potential avenues through which they operate. The authors also highlight how their findings suggest genetic factors may promote upward social mobility noting that: “some individuals who are born into socially disadvantaged families but surpass the constraints typically associated with low socioeconomic status do this in part because of their genetic propensities”
When it comes to educational attainment, research in behavioural genetics tells us it is the interplay of genetic and environmental factors that is key – pitting nature against nurture is a mistake when we know both matter. – Yours, etc,
Associate Prof MICHAEL
DALY,
Department of Psychology,
Maynooth University,
Co Kildare.