Background: Cytochrome P450 2C9 (CYP450 2C9) has an important role in metabolic
processes. Mutations in CYP450 2C9 genes may affect the catalytic activity of this enzyme. The aim
of the present study is to assess the genetic polymorphisms of Cytochrome P450 (2C9) enzyme in
Turkmen and Fars ethnic groups with type 2 diabetes compared with controls.
Methods: A total of 336 Turkmen and 336 Fars type 2 diabetic patients and 336 healthy Turkmen and
Fars individuals were included in this study. Genomic DNA was extracted from whole blood samples
and then the CYP2C9 genotyping was done using the Polymerase Chain Reaction-Restriction Fragment
Length Polymorphism technique.
Results: The CYP2C9*1, CYP2C9*2 and CYP2C9*3 allele frequencies in type 2 diabetic patients
were 85.27%, 11.68%, and 3.05%, and in control were 87.13%, 8.56%, and 4.31%, respectively. We
found significant differences between allele distribution of 2C9 in type 2 diabetic patients and controls.
CYP2C9*2 and CYP2C9*3 allele frequency was significantly different in Turkmen and Fars type 2
diabetic compared to two ethnic controls. The CYP2C9*1/*1 and CYP2C9*1/*2 genotypes frequencies
in type 2 diabetic Turkmen showed significant differences compared to Turkmen control. There
were significant differences in the genotype frequency of CYP2C9*1/*1, CYP2C9*1/*2,
CYP2C9*1/*3, CYP2C9*2/*2, and CYP2C9*2/*3 between type 2 diabetic Fars and Fars controls.
Two diabetic ethnic groups showed statistically significant differences in frequencies of CYP2C9*2/*2
and CYP2C9*2/*3 genotypes.
Conclusion: Our study suggests that diabetic patients with mutant CYP2C9 polymorphism may show
different antidiabetic drug metabolism compared to the wild-type allele. In this regard, determination
of CYP2C9 alleles and genotypes can be a useful tool for the treatment of diabetic patients with antidiabetic
drugs because it may assist physicians’ to determine optimal dosage and efficiency of drugs
metabolized by this polymorphic enzyme.