Association of Common Variants of FGF21 Gene Polymorphism Rs499765 and Rs838133 with Type 2 Diabetes Mellitus in Iraqi Population

  • Majid Kadhum Hussain
  • Abdulhusein A. F. Algenabi
  • Thakra Al-Kashwan
  • Rasha Mohamed Abood


SUMMERY  Background: Type 2 diabetes mellitus is a major public health issue. FGF21 is a key endocrine regulating protein factor involved in ontogenesis and metabolism.  Aim: To assess the association of FGF21 gene polymorphism (rs499765 and rs838133) in Iraqi type 2 diabetic patients.  Methods: To assess the relationship between SNPs (rs499765 and rs838133) of the FGF21 gene and T2DM, a case-control study of 200 people (100 T2DM and 100 controls) was undertaken. Tetra ARMS-PCR was used to genotype SNPs (rs499765 and rs838133) using specified primers after extracting DNA from blood. Various statistical analyses were used to analyze the results. Results: The differences in total cholesterol, VLDL, TG and HDL between healthy and diabetic groups are significant. Genotyping of FGF21 gene for rs838133 SNP revealed a significant elevation of the number of the AC carriers in the patient's group versus the controls group under the co-dominant model, the dominant model and the over dominant were significantly increased the risk of T2DM by 1.91, 1.8 and 1.94 folds (OR=1.91, P=0.0320), (OR=1.87, P=0.037) and (OR=1.94, P=0.0270) respectively. The analysis of the rs499765 SNP failed to exhibit a significant variation under all examined inheritance models.   Conclusion: Carriers of the AC genotype of rs838133 SNP in FGF21 gene have a 1.9 folds risk to develop T2DM in comparison to those of the wild genotype, rs499765 (C>G), is not linked to the T2DM in the Iraqi population.


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