Gene variation of the transient receptor potential cation channel, subfamily M, member 2 (TRPM2) and type 2 diabetes mellitus: A case–control study

BackgroundDisordered cellular calcium regulation has been implicated in the pathophysiology of diabetes through mechanisms that remain unresolved. The non-selective calcium channel, transient receptor potential cation channel, subfamily M, member 2 (TRPM2), has been recently reported to play a role in insulin secretion by pancreatic β-cells. We hypothesized that gene variation of TRPM2 may play a role in the pathophysiology of type 2 diabetes mellitus (T2DM).MethodsUsing a case–control study from a community-based population sample of the Boston metropolitan area (all whites: 455 controls and 467 cases), we assessed the relationship of 9 TRPM2 tag-SNPs with (i) diabetes-related intermediate phenotypes and (ii) the presence of T2DM.ResultAll SNPs examined were in Hardy–Weinberg equilibrium. Overall allele, genotype, and haplotype distributions were similar between cases and controls. Three TRPM2 variants (rs2838553, rs2838554 and rs4818917) were associated with homeostasis model assessment of β-cell function (HOMA-%B), but not with HOMA-insulin resistance (HOMA-IR), fasting glucose levels nor hemoglobin A1c levels. Marker-by-marker logistic regression analysis, adjusted for potential risk factors, showed no evidence for an association of any of the tag-SNPs tested with T2DM. Further investigation using an entropy blocker-defined haplotype-based approach showed similar null findings.ConclusionsThe present investigation found no evidence for an association of the variants tested with T2DM, although HOMA-%B was negatively associated with three TRPM2 variants (rs2838553, rs2838554 and rs4818917). More importantly, our present findings require replication/confirmation in future large-scale, prospective investigations.