I27L Polymorphism in hepatocyte nuclear factor-1α gene and type 2 diabetes mellitus: A meta-analysis of studies about orient population (Chinese and Japanese)

AimsThe aim of the study was to investigate the relationship between I27L variant of HNF-1α gene and type 2 diabetes mellitus (T2DM) in an/the oriental population.MethodsWe recruited 149 T2DM patients and 96 non-diabetes controls from China. The I27L polymorphism in HNF-1α gene was detected by PCR–RFLP analysis. A mete-analysis of previously published studies on I27L and T2DM of orient population and our new study was performed. Databases of MEDLINE, CBM, and the Cochrane Library (CD-ROM) were electronically searched from January 1980 to April 2008. Analysis was performed by RevMan 4.2 software which was downloaded from website of Cochrane collaboration.Results(1). The genotype distribution of I27L/exon1 polymorphism in the HNF-1α gene was in Hardy–Weinberg equilibrium (χ2 = 2.34, 0.05 < P < 0.1). The IL, LL genotype frequencies and L allelic frequency were slightly higher in T2DM group than in controls (0.52, 0.14 and 0.40 in T2DM vs. 0.49, 0.08 and 0.33 in controls), but the difference were not statistically significant, which indicated that 27L variant did not increase the risk of T2DM in our small sample Chinese population. (2). Three published studies concerning the Chinese population, two studies involving the Japanese population and our present study, providing information on a total of 1225 unique subjects, were included in the meta-analysis. The results showed that the 27L variant increased the prevalence of T2DM (OR 1.22, 95% CI 1.03–1.44, p = 0.02).ConclusionI27L polymorphism in the HNF-1α gene increases the risk of T2DM in the orient population (Chinese and Japanese).