Small Ubiquitin-Like Modifier 4 (SUMO4) Gene M55V Polymorphism and Type 2 Diabetes Mellitus: A Meta-analysis Including 6,823 Subjects

BACKGROUND: Many studies suggest that the small ubiquitin-like modifier 4 (SUMO4) M55V gene polymorphism (rs237025) may be associated with an increased risk of type 2 diabetes mellitus (T2DM). However, due to other conflicting results, a clear consensus is lacking in the matter. OBJECTIVE AND METHODS: A meta-analysis consisting of 6,823 subjects from 10 studies was conducted to elucidate relationship between the SUMO4 M55V gene polymorphism and T2DM. Depending on the heterogeneity of the data, either a fixed or random-effects model would be used to assess the combined odds ratio (ORs) and their corresponding 95% confidence interval (CI). RESULTS: SUMO4 gene M55V polymorphism was significantly associated with T2DM in the whole population under allelic (OR: 1.18, 95% CI: 1.10–1.28, P = 1.63 × 10(−5)), recessive (OR: 1.59, 95% CI: 1.14–2.23, P = 0.006), dominant (OR: 0.815, 95% CI: 0.737–0.901, P = 6.89 × 10(−5)), homozygous (OR: 1.415, 95% CI: 1.170–1.710, P = 0.0003), heterozygous (OR: 1.191, 95% CI: 1.072–1.323, P = 0.001), and additive genetic models (OR: 1.184, 95% CI: 1.097–1.279, P = 1.63 × 10(−5)). In our subgroup analysis, a significant association was found again in the Chinese population, but not in Japanese or Iranian population. CONCLUSION: SUMO4 gene M55V polymorphism may correlate with increased T2DM risk. Chinese carriers of the V allele of the SUMO4 gene M55V polymorphism may be predisposed to developing T2DM.