Abstract
Purpose :
Genome-wide association studies have been successful in identifying genetic loci associated with vertical cup-disc ratio (VCDR), yet current findings explain only a limited proportion of the heritability for this trait. Gene-environment (G×E) interaction analysis represents a strategy to identify additional genetic variants and explain the remaining missing heritability. There is compelling evidence that body mass index (BMI) is associated with VCDR.Here, we describe the first genome-wide gene-environment interaction analysis of VCDR by BMI in a Latino population.
Methods :
We conducted a two-step genome-wide gene-environment interaction analysis using 3,927 Latinos genotyped using either the Illumina OmniExpress BeadChip (~730K markers) or the Illumina Hispanic/SOL BeadChip (~2.5 million markers) and imputed based on the 1000 Genomes Project reference panels. Linear regression, adjusting for age, gender, and principal components of genetic ancestry, was performed to assess the associations between all single nucleotide polymorphisms (SNPs) and VCDR during step 1 and those SNPs meeting a pre-determined significance threshold were formally tested for SNP×BMI interaction in step 2.
Results :
We identified three suggestive SNP×BMI interaction associations (P~10-6), indicating the effect of SNPs on VCDR maybe modified by BMI. In stratified analysis, the minor alleles of rs17384023 in TNFSF13B-MYO16and rs1420101 in IL1RL1resulted in lower VCDR among under/normal weight individuals, whereas the minor allele of rs1229982 in ADH1B-ADH1C, yielded a larger VCDR in the same stratum.
Conclusions :
We performed the first genome-wide gene-environment interaction analysis of vertical cup-disc ratio by body mass index. We identified several suggestive associations between SNPs and BMI on VCDR. These findings represent biologically plausible candidate genomic regions for further investigation and exemplify the potential utility of G×E studies to identify additional genetic variants associated with VCDR.
This is a 2020 ARVO Annual Meeting abstract.