Investigation of the association between all-trans-retinol dehydrogenase (RDH8) polymorphisms and high myopia in Chinese

Retinoic acid level in the retina/choroid is altered in induced myopia models.All-trans-retinol dehydrogenase(RDH8) is an important enzyme of retinoic acid metabolism.This study aimed to investigate the association of the RDH8 gene with high myopia.Three single nucleotide polymorphisms(SNPs) [RDH851(rs2233789) ,RDH8E5a(rs1644731) ,and RDH855b(rs3760753) ]were selected,based on the linkage disequilibrium pattern of RDH8 from a previous study,and genotyped for 160 Han Chinese nuclear families with highly myopic(-10 diopters or worse) offspring as well as in an independent group with 166 highly myopic cases(-10 diopters or worse) and 211 controls. Family-based association analysis was performed using the family-based association test(FBAT) package,and genotype relative risk(GRR) was calculated using the GenAssoc program.Population-based association analysis was performed using Chi-square test.These SNPs were in linkage equilibrium with each other.SNPs RDH851(rs2233789) and RDH8E5a(rs1644731) both did not show association with high myopia.SNP RDH855b(rs3760753) demonstrated significant association(P=0.0269) with a GRR of 0.543(95%confidence interval=0.304-0.968,P=0.038) .The association became statistically insignificant,however,after multiple comparison correction.Haplotype analysis did not show a significant association either.Population-based association analysis also showed no significant association(P>0.05) .Our family-and population-based data both suggest that the RDH8 gene is unlikely to be associated with high myopia in Chinese.