19 February 2007
ByAppeared in BioNews 395
Recent research published online in the journal Nature has mapped the most important genes involved in increasing people's risk of developing type 2 diabetes. These genes could account for up to 70 per cent of the genetic risk of developing the disorder.
Type 2 diabetes affects over 1.9 million people in the UK. People with diabetes cannot regulate their blood sugar levels properly, either because their pancreas is not making enough insulin, or because the body becomes resistant to its effects. Type 2 diabetes usually affects people over the age of 40. It is more common in overweight, inactive people, and those with a family history of the disease.
The research, carried out by scientists working at Imperial College London and their French and Canadian collaborators, used a technology called 'high density microarrays' which allows researchers to examine hundreds of different genetic variations relatively quickly. Researchers were able to compare the genetic profile of 700 type 2 diabetes patients with a family history of the condition with 700 healthy counterparts. They discovered four points on the human gene map which differed between the two groups. When particular variants of these four genes are expressed, they confer an increased risk of developing type 2 diabetes. The researchers confirmed their findings by analysing the genetic makeup of a further 5,000 individuals with type 2 diabetes and a family history of the disorder, to verify that the same genetic mutations were visible in these individuals.
One of the four genes highlighted codes for a 'zinc transporter' protein called SLC30A8 which is involved in the control of insulin secretion. They also confirmed a link with a gene called TCF7L2 which has been associated with type 2 diabetes previously.
Professor Philippe Froguel, of the division of Medicine at Imperial College London said, 'If we can tell someone that their genetics mean they are pre-disposed towards type 2 diabetes, they will be much more motivated to change things such as their diet to reduce their chances of developing the disorder. We can also use what we know about the specific genetic mutations associated with type 2 diabetes to develop better treatments'.