Objectives: Insulin-like growth factor 1 (IGF1) and insulin-like growth factor 1 receptor (IGF1R) have been shown to influence the development of form-deprivation myopia. However, genetic association between these two genes and high myopia remains inconsistent in different studies. This study was conducted to investigate the association between IGF1and IGF1R and high myopia in a Han Chinese population.
Methods: Fourteen single nucleotide polymorphisms (SNPs) in the IGF1 and IGF1R genes were genotyped by SNaPshot method in a Han Chinese subject group composed of 1244 high myopia patients and 1380 controls. The genotyping data was analyzed by χ2 test and the linkage disequilibrium block structure was examined by Haploview software.
Results: There were no statistically significant differences in the allele frequencies of IGF1 and IGF1R SNPs and genotypes between patients and controls after Bonferroni multiple-correction (p > 0.05). However, the G allele of rs35766 in the IGF1 gene showed a protective effect for high myopia (p = 0.015, corrected p = 0.21, odds ratio [OR] = 0.77, 95% CI = 0.70-0.97). The carriers of rs35766GG and rs35766GG+AG genotypes displayed a decreased risk of high myopia compared with rs35766AA carriers (p = 0.012, OR = 0.65, 95% CI = 0.47-0.91; p = 0.019, OR = 0.68, 95% CI = 0.50-0.94, respectively).
Conclusions: Genetic variants in the IGF1 and IGF1R genes might not be associated with high myopia in Han Chinese. Further studies are needed to verify the possible function of IGF1 and IGF1R in the development of myopia.
Keywords: High myopia; IGF1; IGF1R; single nucleotide polymorphisms.