Pilot studies on the prevalence and association of TCF7L2 polymorphisms in non-diabetic participants and type 2 diabetic patients of South Tamil Nadu

Balaji Ramanathan, Jeyasudha Murugan, Kumaravel Velayutham, Vishali Thavamani, Rajamanickam Chellam, Rohini Gomathinayagam


Background: Genetic predisposition plays a critical role in the incidence of type 2 diabetes mellitus (T2DM). While a few reports strongly associate TCF7L2 gene polymorphisms in the T2DM incidence in India, data pertaining to the prevalence of these polymorphisms in the south Tamil Nadu population has been lacking. Hence, the present study aims to determine the prevalence and association of the TCF7L2 gene variants rs7903146, rs12255372 in the regional population of south Tamil Nadu.

Methods: Peripheral blood samples from controls, T2DM patients were utilized to isolate genomic DNA and genotyping was carried out using PCR based strategies, direct sequencing. Socio-demographic details, anthropometric measurements, determination of postprandial, random blood glucose levels and oral glucose tolerance test (OGTT) were further carried out to evaluate the predisposition risk for T2DM.

Results: 50% of the control group participants and 73.9% of the T2DM patients were positive (CT/TT) for the TCF7L2 polymorphism rs7903146. The rs12255372 SNP was less prevalent in the controls, patients and was dispersed in only 25% of the controls and 60.9% (GT/TT) of the patients. The 60 minutes plasma glucose levels for the oral glucose tolerance test (OGTT) was higher (143.3±19.8) in the rs7903146 and rs12255372 positive control participants.

Conclusions: The study results reveal that TCF7L2 polymorphisms are dispersed in the regional population and further large scale, long term follow up studies will aid preventive and therapeutic measures in T2DM.


TCF7L2, Genetic predisposition, rs7903146, rs12255372, T2DM

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