Heritability of individual visual abilities captured by common SNPs

Vision research is a major topic in cognitive sciences. During the last decades, it has become a well developed research field in human neuroscience. Up to now, common visual abilities and visual phenomena have been well studied at the level of behavioral characteristics, neuronal basis, and computational modeling. In contrast, the molecular mechanisms underlying these visual phenomena have rarely been studied. A recent study has explored the heritability of binocular rivalry in twins, and has found that 52% of the phenotypic variance could be attributed to genetic factors. Here, we extended the study by exploring the narrow heritability of a bunch of visual abilities (perceptual grouping, orientation discrimination, motion discrimination, and motion detection) and vision-related phenomena (binocular rivalry, bistable perception, and Ebbinghaus illusion) in normal human subjects. We did genome-wide restricted maximum likelihood (GREML) analysis on 819,711 common SNPs. Results showed that, for perceptual grouping (70%, s.e.=0.297, n=1185), orientation discrimination (60%, s.e.=0.48, n=802), and bistable perception (89%, s.e.=0.32, n=1246), more than half of the variance could be explained by all the tested SNPs. For motion discrimination (39%, s.e.=0.34, n=1235), motion detection (37%, s.e.=0.35, n=1197), binocular rivalry (42%, s.e.=0.28, n=1369), and Ebbinghaus illusion (18%, s.e.=0.27, n=1339), the narrow heritability was smaller yet still no less than 18%. Furthermore, because the explained variance by GREML came only from contribution of all the common SNPs, the true estimated heritability of these visual phenotypes should be larger. Therefore, visual behavior might be highly heritable, and part of the variance in the visual phenomena could even be well explained by common SNPs. Taken together, these findings indicate that further studies focusing on the molecular mechanisms behind visual abilities and phenomena are needed, especially for those with high heritability (e.g. perceptual grouping, motion detection, orientation discrimination, bistable perception, and so on). Meeting abstract presented at VSS 2016