Resistin gene polymorphisms and progression of glycaemia in southern Chinese: A 5-year prospective study

Abstract

Objective: Human resistin gene (RETN) polymorphisms have been found to be associated with type 2 diabetes (T2DM), insulin resistance and/or obesity. We evaluated, in a 5-year prospective study, whether RETN polymorphisms could predict the progression of glycaemia in southern Chinese. Design and patients: We conducted a systematic search for variants in RETN in 70 southern Chinese subjects. This was followed by the genotyping in 624 unrelated nondiabetic subjects of two polymorphisms, -420C→G and +62G→A, previously reported in cross-sectional studies to be associated with T2DM in Asians, to examine their relationship with the progression of glycaemia in this cohort. Results: We identified 15 polymorphisms, including 2 novel but rare polymorphisms (-319G→A and +63G→C). Compared to subjects with the CC genotype, -420GG subjects had higher 2-h glucose (7.7 ± 1.8 vs. 7.2 ± 2.0 mmol/l, P = 0.011) and insulin (101.6 ± 69.5 vs. 79.8 ± 59.5 mU/l, P = 0.021) during an oral glucose tolerance test. Carriers of the +62A allele had higher body mass indices (25.3 ± 4.0 vs. 24.5 ± 3.6 kg/m 2 in GG, P = 0.02). The presence of the allele -420G (OR 2.15, 95% CI 1.28-3.60, P = 0.004) or +62A (OR1.86, 95% CI 1.08-3.21, P = 0.025) predicted the progression of glycaemia at Year 5, after adjustment for sex, age or body mass index. The haplotype G-A also conferred a higher risk of progression in glycaemia (P = 0.002). Conclusion: Our study would support the role of the resistin gene in obesity, insulin resistance and progression of glycaemia in southern Chinese. © 2006 The Authors.