Summary: Eye color is highly variable in populations with European ancestry, ranging from low to high quantities of melanin in the iris.Polymorphisms in the HERC2/OCA2 locus have the largest effect on eye color in these populations, although other genomic regions click here also influence eye color.We performed genome-wide association studies of eye color in a Canadian cohort of European ancestry (N = 5,641) and investigated candidate causal variants.We uncovered several candidate causal signals in the HERC2/OCA2 region, whereas other loci likely harbor a single causal signal.We observed colocalization of eye color signals with the expression or methylation profiles of cultured primary melanocytes.
Genetic correlations of eye and bostik roll-cote hair color suggest high genome-wide pleiotropy, but locus-level differences in the genetic architecture of both traits.Overall, we provide a better picture of the polymorphisms underpinning eye color variation, which may be a consequence of specific molecular processes in the iris melanocytes.