Association of rs7260002 of chorionic gonadotrophin β5 with idiopathic recurrent spontaneous abortion in Chinese population

Abstract

Purpose Low levels of serum hCG during the first trimester is regarded as a predictor of miscarriage. This study was designed to examine whether variance in chorionic gonadotrophin β5 (Cgb5) gene confers risk to recurrent spontaneous abortions (RSA) in Chinese women. Methods We recruited a total of 454 RSA subjects and 460 controls from our medical center between the years 2010 to 2013. rs7260002, which resides in the promoter region of Cgb5, was genotyped through direct sequencing. Results The carriers with the minor allele of rs7260002 had reduced risk of RSA (P=0.018; P adjusted=0.032; OR: 0.76; 95 % CI: 0.61-0.96). Genotype frequency was further analyzed under additive, recessive, and dominant models. Significant differences between the RSA subjects and controls were detected under additive and recessive models (P additive= 0.040; P recessive=0.010). Conclusions The current study identified a protective allele of the Cgb5 gene against RSA. Functional studies are required to elucidate the effect of the identified SNP on CGB expression and HCG hormone activity.

Impact of gene polymorphisms of gonadotropins and their receptors on human reproductive success

“…The human genome carries eight CGB genes contiguous with the LHB gene on chromosome 19; subsequently, frame-shift mutations and nucleotide insertions resulted in 24 additional codons for CGB. The LHB/CGB gene cluster spans about 40 kbp and carries several SNPs; especially, polymorphic variants of the CGB5 were associated with recurrent spontaneous abortions in Chinese and Caucasian women (Rull et al 2008, Sun & Ji 2014.…”