Researchers nail down six genetic variants for diabetes
Imperial College of London-led study identifies six potential causative agents of type 2 diabetes in South Asian populations
In one of the most recent developments in the field ofdiabetes and related genes, a team of researchers led by Imperial CollegeLondon has identified six new genetic variants that might be causative agentsof type 2 diabetes in South Asian populations such as Pakistani, Indian,Bangladeshi and Sri Lankan. The discoveries were published in Nature Genetics and stand to provide newclues and directional focus in the search for diagnostic markers as well asdrug targets for diabetes, which afflicts approximately 400 million peopleworldwide.
"Genetic factors have been widely considered to play a rolein the increased risk of type 2 diabetes in Asians, but to date have not beensystematically explored in this population," Dr. John Chambers, of the Schoolof Public Health at Imperial College London, said in a press release. Chambersis the senior author of the study. "Our study identifies six new geneticvariants linked to type 2 diabetes in South Asians. Our findings give importantnew insight into the genes underlying of diabetes in this population, which inthe long term might lead to new treatments to prevent diabetes."
The study is the first to focus on diabetes-related genes inpeople of South Asian origin, who are up to four times more likely to developtype 2 diabetes than Europeans. Nearly 55 million South Asians are affectedworldwide, with that number forecasted to increase to over 80 million by 2030.
In an examination of the DNA of 18,731 people with type 2diabetes and 39,856 healthy controls, the researchers focused on the patients'genomes to look for locations of DNA sequences where variations were moreprevalent in those with diabetes. As a result, six positions were identifiedwhere differences of just a single letter in the DNA were associated with type2 diabetes, bringing nearby genes into focus as possibly having a hand indiabetes.
"This is the first genome-wide association study in SouthAsians, who comprise one-quarter of the globe's population, and who carry ahigh burden of the disease and its complications, including heart attack andstroke," Jaspal S. Kooner, of the National Heart and Lung Institute at ImperialCollege London, said in a press release. Kooner was the lead author for thestudy. "We have shown that the genetic variants discovered here in South Asiansalso exist and contribute to diabetes in Europeans. Our studies in Asians andEuropean populations highlight the importance and gain in examining the sameproblem in different ethnic groups."
The study is one of the most recent efforts in uncoveringgenetic links to diabetes. Another study by the University of Wisconsin-Madisonresulted in the identification of a gene that could provide answers as to whysome people are more susceptible to diabetes than others. The gene controls aprotein known as tomosyn-2, which works as a brake on pancreatic insulinsecretion. In tests on obese mice, it was discovered that a single amino aciddifference that destabilizes tomosyn-2 in diabetes-resistant mice allows themto secrete enough insulin to avoid diabetes.
The discovery by the Imperial College researchers couldhopefully lead to similar discoveries for other ethnic groups, or eventuallyuniversal genetic markers, for disease prediction or earlier treatment fordiabetes.