Genetic variants associated with central corneal thickness in Latinos

Abstract

Purpose: : Central corneal thickness (CCT) is an important risk factor for primary open angle glaucoma (POAG), one of the most challenging vision disorders. The identification of genetic variants associated with CCT can provide insights to the pathogenesis of POAG. Here we describe the first GWAS report of CCT in Latinos, the most populous minority population in the US.

Methods: : We conducted a population-based genome-wide association study (GWAS) for CCT using our first batch genotyping of 665 Latinos recruited in the Los Angeles Latino Eye Study (LALES). We are expanding our GWAS to a second batch of 1,300 Latinos in LALES. The data were genotyped using the Illumina HumanOmniExpress Beadchip (~730K markers). All subjects aged 40 years and older. We used linear regression with adjustment for age, sex and principal components of genetic ancestry. All statistical regression analyses were performed using PLINK.

Results: : In our first batch of GWAS, we replicated the involvement of a previously reported gene, COL5A1, on chromosome 9 for CCT (P = 4.04 x10^-6), which was originally reported in Europeans and recently replicated in Asians. Moreover, we discovered several other novel significant loci on chromosome 16 for CCT in Latinos (P ~ 10^-7).

Conclusions: : Studies of genes that control CCT not only offer insights in the molecular regulatory mechanism of CCT but also provide candidate genes for further investigation of POAG.

Keywords: genetics • gene mapping • cornea: basic science