Diabetes is a chronic metabolic disorder and it is increasing worldwide. Type 2 Diabetes Mellitus is the major type of diabetes and is also known as non-insulin dependent diabetes mellitus (NIDDM). The pathogenesis of T2DM is controversial and seems to involve genetic and environmental factors, including family history, obesity, hypertension, etc. DNase I gene encodes for deoxyribonuclease I that degrades double stranded DNA during apoptosis. This study is based on family history of T2DM and the role of DNase I gene. Method: The blood samples of Type 2 Diabetic patients with a strong family history were collected and DNA was isolated by the proteins K method. PCR was performed to amplify the specific region (exon 8) of the DNase I gene and amplified products were sequenced. Results: The sequenced data were analyzed by NCBI Blast software and no mutation was observed in any of the samples. The samples enrolled in this study had a strong family history of T2DM and pedigrees were drawn. Conclusion: Type 2 Diabetes Mellitus was not associated with BMI but it is strongly associated with hypertension. DNase I gene seems to be not involved in the pathogenesis of Type 2 Diabetes Mellitus.