Genetic insights into foveal morphology and its associations with pigmentation and age-related macular degeneration.

The fovea is the small depression at the neurosensory retina that underlies high-resolution central vision. It is vulnerable to disease and disruption of its architecture causes visual disability. Foveal morphology varies significantly across individuals. The molecular causes and functional consequences of this anatomical diversity are incompletely understood. Here, we extracted six foveal morphological parameters from Optical Coherence Tomography (OCT) images of 55,604 UK Biobank participants. We found notable variability in foveal morphology, and detected significant links with sex and genetic ancestry. Genome-wide association studies identified 197 lead loci across the six foveal morphological parameters, implicating genes involved in pigmentation (e.g., TYR, TSPAN10, GPR143) and patterning (e.g., FGFR2, PTPRD, CYP1A1). Heritability estimates ranged from 29-43%. Foveal pit volume was associated with future risk of age-related macular degeneration (HR>3.5, p=0.001), a finding supported by Mendelian randomization. These results establish foveal morphology as a highly-heritable trait with substantial influence over retinal disease risk.