Effects of variation in retinol binding protein 4 gene and adipose specific expression of gestational diabetes in Beijing, China

Objective: To investigate the clinical features of GDM in China and the effects of RBP4 genetic variants, and also to identify RBP4 expression changes in mRNA and protein levels. Research design and methods: 1595 Chinese pregnant women were included in this study. Four known RBP4 single nucleotide polymorphisms (SNPs) were genotyped in 505 cases and 687 controls. Expression levels of adipose specific RBP4 mRNA and protein were detected in 41 samples of subcutaneous adipose tissue. Results: The estimated indices of insulin resistance were gradually increased from NGT, GIGT to GDM. Two single SNPs were associated with GDM (rs3758539 G vs A, OR = 1.446, P = 0.009; rs3758539 GG vs AG + AA, OR = 1.532, P = 0.006; rs12265684 C vs G, OR = 1.296, P = 0.038) and a haplotype of 3 common SNPs [G-G-T] was increased in subjects with GDM and GIGT (OR = 1.322, 95% CI 1.054-1.659, P = 0.016). RBP4 mRNA expression in adipose tissue of GDM patients was significantly increased in comparison to control subjects (1.438 +/- 0.187 vs 1.034 +/- 0.062, p = 0.025). Conclusion: This finding suggests that impaired insulin sensitivity has an early onset in mild gestational intolerance. Two single SNPs were associated with GDM in the case-control study while a haplotype of 3 common SNPs [G-G-T] was increased in glucose intolerance subjects. (C) 2012 Elsevier Ireland Ltd. All rights reserved.