Obesity

Obesity a common nutritional disorder which affects approximately 30% of adults in the Western World. Obesity is a complex disorder in which genetic susceptibility to environmental trigger's being implicated as a cause. Studies on adopted children have illustrated that obesity in adults arises from a genetic predisposition rather than childhood environment. Such a genetic predisposition may be identified by DNA studies. Obesity tends to occur together with dyslipidemia, non-insulin-dependent diabetes mellitus, hypertension and impaired glucose intolerance in a disorder collectively known as Syndrome x.

Low density lipoprotein receptor (LDLR) gene is responsible for the regulation of low density lipoprotein (LDL) levels which transport plasma lipids and cholesterol throughout the blood. Gene defects in LDLR may interfere with this regulation. Since lipoprotein concentration is proportional to abdominal fat deposition in obese individuals.

In our cross-sectional study, the low density lipoprotein receptor (LDLR) gene locus was analysed for its involvement in obesity. Previous studies on LDLR polymorphisms have illustrated associations between polymorphisms located towards the 5’ end of of the gene, and obesity in hypertensives. Studies have also illustrated that lipoprotein concentration in the blood is proportional to abdominal fat deposition in obese individuals.

Results from our study indicated a significant association (X2 = 7.09, P = 0.0298) between LDLR microsatellite marker located towards the 3’ end of the gene and obesity. ANOVA analysis between lean and obese individuals also illustrated that the obese individuals had higher cholesterol, triglyceride and LDL-cholesterol levels which may arise from an impaired LDL receptor regulation and a lower HDL-cholesterol levels than lean individuals. These results confirm that there is an association between an LDLR microsatellite polymorphism and obesity indicating that this gene may play an important role in obesity predisposition.