A new study led by researchers at the McGill University Health Centre (MUHC) has identified four genes that increase the risk of developing type 2 diabetes. This form of diabetes is the most common worldwide and affects nearly 2 million Canadians. In recent years, the prevalence of Type 2 diabetes has increased rapidly. This genetic discovery may help stem this rise.
This genetic study, published today in the journal Nature, was led by MUHC endocrinologist Dr. Rob Sladek at the McGill University and Genome Quebec Innovation Centre together with Dr. Constantin Polychronakos at the MUHC and Dr. Philippe Froguel at the Pasteur Institute (Lille, France). The study also involved scientists at the University of Montreal, Imperial College (London, UK) and the Montreal Diabetes Research Centre.
Sladek and his colleagues systematically searched the entire human genome to identify genes that predispose individuals to developing diabetes. By comparing hundreds of thousands of DNA fragments from patients with diabetes to those from non-diabetic individuals, they discovered that patients who developed diabetes shared common gene variants on chromosomes 8, 10 and 11.
"Of the four genes we have identified, two are involved in the development or function of insulin-secreting cells and one plays a role in the transport of zinc, an important mineral required for the production of insulin," says Sladek.
"We used a totally new concept and technology to look for the genes," says Polychronakos. "It worked very successfully and our findings are proof of principle that these approaches can be used to dissect the genetic component of other complex diseases and, eventually, other complex human traits."
Type 2 diabetes is the most common form of diabetes in adults and is becoming increasingly common in children. It is caused by the decreased production or effect of insulin, a hormone that is secreted by the pancreas and which regulates the amount of glucose in the blood. It has been known for some time that for Type 2 diabetes is caused by a combination of genetic and lifestyle factors. The group's new finding helps identify the population at the highest risk of developing this disease.
The research was funded by a grant from Genome Canada and Genome Quebec headed by Dr. Barry I. Posner, professor of Medicine at McGill University and the MUHC; and by a grant from the Canadian Foundation for Innovation to the Montreal Diabetes Research Centre, headed by Dr. Marc Prentki, professor of Medicine at the University of Montreal.
"In the last few years, advances in technology pioneered in Quebec, have made complex genetic analyses, such as those used in this study, possible," stated Genome Quebec President Paul L'Archeveque. "Without these advances an the collaboration between institutes, this research would not have been possible. The experimental approach used in this study, may help lead to the unraveling of other complex genetic diseases."