Vizag links obesity, diabetes

December 23, 2007
By Syed Akbar
Hyderabad, Dec 22: Researchers from Andhra University have discovered the specific genetic link between obesity and diabetes mellitus or type-2 diabetes. Though obesity has oft been linked to type 2 diabetes (patients suffering from this type of diabetes need no insulin), there has been no conclusive data on how it works out.
Obesity is an important component of metabolic syndrome X and predisposes to the development of type 2 diabetes. Moreover, it is not clear how genetic factors interact with environmental and dietary factors to increase the incidence. Andhra University researchers have found a genetic link between overweight and diabetes mellitus.
The study gains significance in the backdrop of Andhra Pradesh gaining the dubious distinction of being the diabetes capital of India. Within Andhra Pradesh, Hyderabad city leads the number of diabetic patients.
The researchers, Undurti N Das and Allam A Rao, performed gene expression profile in subjects with obesity and type 2 diabetes with and without family history of the disease. They noted that genes involved in carbohydrate, lipid and amino acid metabolism pathways and other factors were upregulated in obesity compared to healthy subjects.
"In contrast genes involved in cell adhesion molecules and insulin signalling and immune system pathways are downregulated in obese. Genes involved in inflammatory pathway are differentially expressed both in obesity and type 2 diabetes. These results suggest that genes concerned with carbohydrate, lipid and amino acid metabolic pathways play a significant role in the pathobiology of obesity and type 2
diabetes," they said.
Dr Das and Dr Rao obtained blood samples from healthy normal, healthy but was overweight, obese, persons with type 2 diabetes with family history and those with type 2 diabetes with no family history of diabetes.
All these subjects were matched for age, gender, and body mass index. RNA was extracted from the peripheral blood leukocytes from these subjects. Gene expression values were obtained for 39,400 genes for each individual. Later, they did a comparison study to arrive at the conclusion that the genes that deal with carbohydrate and other metabolic pathways in obese persons lead to diabetes mellitus.