Identification of a candidate gene for astigmatism.

Publications // Young Lab // Feb 01 2013

PubMed ID: 23322567

Author(s): Lopes MC, Hysi PG, Verhoeven VJ, Macgregor S, Hewitt AW, Montgomery GW, Cumberland P, Vingerling JR, Young TL, van Duijn CM, Oostra B, Uitterlinden AG, Rahi JS, Mackey DA, Klaver CC, Andrew T, Hammond CJ. Identification of a candidate gene for astigmatism. Invest Ophthalmol Vis Sci. 2013 Feb 1;54(2):1260-7. doi: 10.1167/iovs.12-10463. PMID 23322567

Journal: Investigative Ophthalmology & Visual Science, Volume 54, Issue 2, Feb 2013

PURPOSE Astigmatism is a common refractive error that reduces vision, where the curvature and refractive power of the cornea in one meridian are less than those of the perpendicular axis. It is a complex trait likely to be influenced by both genetic and environmental factors. Twin studies of astigmatism have found approximately 60% of phenotypic variance is explained by genetic factors. This study aimed to identify susceptibility loci for astigmatism.

METHODS We performed a meta-analysis of seven genome-wide association studies that included 22,100 individuals of European descent, where astigmatism was defined as the number of diopters of cylinder prescription, using fixed effect inverse variance-weighted methods.

RESULTS A susceptibility locus was identified with lead single nucleotide polymorphism rs3771395 on chromosome 2p13.3 (meta-analysis, P = 1.97 × 10(-7)) in the VAX2 gene. VAX2 plays an important role in the development of the dorsoventral axis of the eye. Animal studies have shown a gradient in astigmatism along the vertical plane, with corresponding changes in refraction, particularly in the ventral field.

CONCLUSIONS This finding advances the understanding of refractive error, and provides new potential pathways to be evaluated with regard to the development of astigmatism.