MRC Integrative Epidemiology Unit (IEU) Seminar Series

Title: Disentangling nature and nurture using genomic family data

Abstract: Heritability measures the relative contribution of genetic inheritance (nature) and environment (nurture) to trait variation. Estimation of heritability is especially challenging when genetic and environmental effects are correlated, such as when indirect genetic effects from relatives are present. An indirect genetic effect on a proband is the effect of a genetic variant on the proband through the proband’s environment, for example occurring when parental nurturing behaviours are influenced by parents’ genes. I show that indirect genetic effects from parents to offspring and between siblings are substantial for educational attainment. Also, when indirect genetic effects from relatives are substantial, some existing methods for estimating heritability can be severely biased. To remedy this, I introduce a novel method for estimating heritability: relatedness disequilibrium regression (RDR). RDR removes environmental bias by exploiting variation in relatedness due to random Mendelian segregations in the probands’ parents. I report results from applying RDR to a sample of 54,888 Icelanders with both parents genotyped to estimate the heritability of 14 traits, including educational attainment, and comparing to heritability estimates from other methods.

Biography: Alexander Young is a postdoctoral researcher at the Big Data Institute, University of Oxford. Alex's research is motivated by the fundamental question of how genetic variation in a population gives rise to trait variation. Alex's background is in mathematics and statistics, tools which he uses to develop novel theory and methods to apply to this problem. Formerly, he worked with Peter Donnelly at the Wellcome Trust Centre for Human Genetics and with Augustine Kong at deCODE Genetics in Iceland.

All welcome