Association between leptin G-2548A gene polymorphism, plasma leptin levels and lipid profiles in Turkish Cypriot obese subjects

Objective: Leptin (LEP) is a metabolic and neuroendocrine hormone which is present in the circulation in amounts proportional to fat mass that acts to reduce food intake and increase energy expenditure thereby regulating body weight homeostasis. Various polymorphisms are shown to be present in LEP gene which play important roles in obesity and obesity-related metabolic biomarkers. The aim of this study was to investigate the association of one of these polymorphisms, leptin gene G-2548A polymorphism, on obesity in association with body mass index (BMI), lipid parameters, plasma leptin levels and homeostasis model assessment of insulin resistance (HOMA-IR). Methods: The study included 110 obese and 90 non-obese subjects. The LEP G-2548A polymorphism was determined by polymerase chain reaction - restriction fragment length polymorphism (PCR-RFLP). Plasma leptin levels, serum lipid and antropometric parameters were measured. Results: No association was found between LEP gene G-2548A polymorphism and BMI in both study and control groups. Strikingly study group with obese subjects and with the AA genotype had significantly higher serum total cholesterol (p<0.05) than GA and GG geno-types. In obese group, subjects with the AA genotypes had significantly higher leptin (p<0.05) levels than the GG and GA genotypes. Conclusion: Our results suggest that the LEP gene G-2548A polymorphism may not be considered as a genetic risk factor for obesity in Turkish Cypriot population. However, the G-2548A polymorphism appear to be important in regulating leptin and total cholesterol levels in obese group through leptin gene expression and signaling.