Influence of PTPN1 polymorphism among people with type 2 diabetes: A Thanjavur-based study

Type 2 diabetes is a multifactorial and polygenic disease that involves insulin resistance and impaired glucose induced insulin release. Besides environmental factors, the influence of genetic changes also drives the susceptibility of the disease. One such attractive candidate gene influencing the glucose metabolism is the gene encoding for protein tyrosine phosphatase 1B (PTPN1), located on the chromosome 20. The gene product is negatively regulating the insulin signaling by dephosphorylating the phosphotyrosine residues of the insulin receptor kinase activation segment. This study examined the association between one of the allelic polymorphisms (−1023C/A) in PTPN1 gene with type 2 diabetes in the local population of Thanjavur, India. Genotypic analysis was performed on 96 diabetic and 96 non-diabetic patients using polymerase chain reaction–based restriction fragment length polymorphism. The frequency of allele A in the homozygous form of −1023C>A polymorphism was found to be lesser (19%) when compared with the control population. In the body mass index (BMI)-based classification, the homozygous A allele was absent in case participants with BMIs lower than 30 but it was present in four of the controls with variant allele. Chi square were used to determine out the significant association of the polymorphism with the disease. There was no statistical significance obtained for the studied population; the result may be validated by analyzing larger sample size in the future.