Abstract
Purpose :
Previous genetic and epidemiological studies have suggested genetics contributes to the development of astigmatism. The purpose of this investigation was to identify genetic variants associated with corneal and refractive astigmatism in a large-scale European ancestry cohort (UK Biobank).
Methods :
Keratometry and autorefractor measurements were obtained during assessment centre visits. Genome-wide association studies for corneal and refractive astigmatism were performed in individuals of European ancestry (N = 86,505 and 88,005 respectively), with the mean corneal astigmatism or refractive astigmatism in fellow eyes analysed as a quantitative trait (dependent variable). Genetic correlation between the two traits was calculated using LD Score regression. Gene-based and gene-set tests were carried out using MAGMA.
Results :
Single marker-based association tests for corneal astigmatism identified four genome-wide significant loci (P < 5 x 10-8) near the genes ZC3H11B (1q41), LINC00340 (6p22.3), HERC2/OCA2 (15q13.1) and NPLOC4/TSPAN10 (17q25.3). Three of these loci also demonstrated genome-wide significant association with refractive astigmatism: LINC00340, HERC2/OCA2 and NPLOC4/TSPAN10. Gene-based and gene-set analyses yielded non-significant findings after correction for multiple testing. The genetic correlation between corneal and refractive astigmatism was 0.85 (SE = 0.068, P = 1.37 x 10-35).
Conclusions :
Here, we have undertaken the largest genome-wide association studies for corneal and refractive astigmatism to date and identified four novel loci for corneal astigmatism, two of which were also novel loci for refractive astigmatism. These loci have previously demonstrated association with axial length (ZC3H11B), myopia (NPLOC4), spherical equivalent (LINC00340) and eye colour (HERC2). The shared role of these novel candidate genes for astigmatism lends further support to the shared genetic susceptibility of myopia and astigmatism.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.