Genotype Phenotype Correlation of Genetic Polymorphism of PPAR Gamma Gene and Therapeutic Response to Pioglitazone in Type 2 Diabetes Mellitus- A Pilot Study
FC11-FC14
Correspondence
Dr. S. Shanmuga Priya,
PSG Institute of Medical Sciences & Research Off Avinashi Road, Peelamedu, Coimbatore-641004, Tamilnadu, India.
E-mail : somasundaram999@rediffmail.com
Introduction: Pro12Ala polymorphism is a missense mutation at codon 12 in peroxisome proliferator-activated receptor ? gene (PPARG). This polymorphism is known to be associated with increased insulin sensitivity. Pioglitazone, a thiazolidinedione, is an anti-diabetic drug which acts as an agonist at PPAR ? receptor.
Aim: To determine the association between Pro12Ala polymorphism of the PPARG and variation in therapeutic response to the PPAR? agonist, pioglitazone.
Materials and Methods: The study was done as a hospital based pilot project in 30 patients with type 2 diabetes mellitus, on treatment with sulfonylurea or metformin but without adequate glycaemic control. They were started on pioglitazone as add on therapy for a period of 12 weeks. The participants were categorized as responders and non-responders based on the change in HbA1C level after 12 weeks. Pro12Ala polymorphism was analysed by polymerase chain reaction-restriction fragment length polymorphism.
Statistical Analysis: Logistic regression analysis was done to evaluate the associations between age, baseline body weight, BMI, waist circumference, waist-hip ratio and Pro12Ala variants with the response to pioglitazone. The p-value< 0.05 was considered significant.
Results: The frequency distributions of PPAR gamma genotypes were 80% for Pro/Pro and 20% for Pro/Ala in the study population. Among the study participants, 30% were non-responders and 70% responders to pioglitazone. A significantly higher frequency of the polymorphism was detected in the responders (p=0.005) compared to non-responders group.
Conclusion: Our study suggests that there is a potential association between Pro12Ala polymorphism and glycaemic response to pioglitazone.