Association of Resistin Gene 3’-Untranslated Region EX4-44G→A Polymorphism with Obesity- and Insulin-Related Phenotypes in Turkish Type 2 Diabetes Patients
Belgin Süsleyici DumanDepartment of Medical Biology and Genetics, Faculty of Medicine, Istanbul Science University, Istanbul, Turkey
Penbe CagatayDepartment of Biostatistics, Cerrahpasa Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Hüsrev HatemiTurkish Diabetes Hospital, Dr. Celal Oker Street. No. 10, Harbiye, Turkey.
Melek ÖztürkDepartment of Medical Biology, Cerrahpasa Faculty of Medicine, Istanbul University, Istanbul, Turkey.
Resistin, an adipocyte-secreted hormone, has been associated with obesity, insulin resistance and type 2 diabetes mellitus (T2DM) in some, but not all, rodent models. In humans, the exact function of resistin is unkown. Because 3’- untranslated region (3’-UTR) single nucleotide substitutions (SNPs) have been shown to affect gene expression, we examined the EX4-44G→A SNP in the 3’-UTR of exon 3 within the resistin gene. The objective of this study was to investigate, for the first time in a Turkish study group, whether the 3’-UTR EX4-44G→A variation in the resistin gene influences the development of T2DM, obesity and insulin-related phenotypes. We analyzed the genotype frequencies of the EX4-44G→A polymorphism of the resistin gene in 116 type 2 diabetic and 102 normal subjects. Serum lipids, obesity-related and insulin-related phenotypes were analyzed. No significant difference for genotypic frequencies were observed for the BseRI restriction site in type 2 diabetic patients as compared to controls. Waist-to-hip ratio, BMI, body fat and apoAI levels were found to be affected by resistin genotype. In the control group, BMI (p < 0.01), HIS (p < 0.05) and BF (p < 0.05) levels were found to be elevated, whereas HOMA β-cell index (p < 0.01) and apo AI (p < 0.05) levels were found to be decreased in GG genotype carriers. In the diabetic group, the GG genotype carriers were found to have higher BMI levels (p<0.001), waistto-hip ratio (p >< 0.05), body fat (p < 0.01), HOMA (p < 0.001) and fasting insulin (p < 0.05), but lower HbA1c levels in comparison to GC + AA carriers. These data suggest that, in the Turkish study group, the EX4-44G→A polymorphism of the resistin gene is associated with insulin and obesity-related phenotypes.
KeywordsEX4-44G→A polymorphism · type 2 diabetes · resistin · obesity · insulin resistance · body fat,.
Rev Diabet Stud