'Carb breakdown' gene key player in obesity

Scientists have discovered that people with fewer copies of a gene coding for a carb-digesting enzyme may be at higher risk of obesity.

The study conducted by King's College London and Imperial College London found that dietary advice may need to be more tailored to an individual's digestive system, based on whether they have the genetic predisposition and necessary enzymes to digest different foods.

According to the study, people with fewer copies of the AMY1 gene have lower levels of this enzyme and therefore will have more difficulty breaking down carbohydrates than those with more copies.

Professor Tim Spector, Head of the Department of Twin Research and Genetic Epidemiology at King's College London said that these findings are very exciting and they have found that the digestive 'tools' in metabolism vary between people and the genes coding for these can have a large influence on weight.

The researchers said that a simple blood or saliva test might be used in the future to measure levels of key enzymes such as amylase in the body and therefore shape dietary advice for both overweight and underweight people.

The study was published in Nature Genetics.