Dynamic genetic regulation of gene expression during cellular differentiation

Variants affect gene expression over time Genetic variation drives the spectrum of human phenotypes but in some cases has been linked to pathological conditions. Strober et al. set out to explore how genetic diversity regulates gene expression in cell differentiation over time. They examined expression quantitative trait loci (eQTLS)—genetic variants correlated with gene expression—in induced pluripotent stem cell lines from 19 Yoruban individuals at 16 time points during differentiation into cardiomyocytes. They identified hundreds of developmental stage–specific eQTLs. Thus, the impact of genetic variations depends on the developmental context or tissue under observation. Science , this issue p. 1287