An international research team has identified seven new gene loci linked to obesity. Researchers were also able to show that the genetic mechanisms that cause extreme obesity are similar to those that cause milder forms of overweight and obesity.
A total of more than 260,000 people were included in the study of the links between genes and obesity, which will be published in the latest issue of Nature Genetics. The aim of the study was to identify new genes that increase the risk of obesity, but also to compare genetic factors that cause extreme obesity with those that are linked to rest of the BMI range.
"We know from experience that genetic factors are important for the emergence of both milder and more extreme forms of obesity, but how much overlap there is between genes that are involved in extreme obesity and normal or slightly elevated BMI has not been examined systematically previously," says Erik Ingelsson, Professor at the Department of Medical Sciences and Science for Life Laboratory, Uppsala University, who coordinated the study.
The researchers studied gene variants, or positions in the genetic code that differ between individuals. Many million such commonly occurring inherited differences are scattered throughout the genome. In the recently published study, researchers identified loci (regions of the genome) that are linked to obesity through examining the relationship between different body measurements and 2.8 million gene variants in 168,267 participants.
They then carried out a targeted follow-up of the 273 gene variants with the strongest link to various body measurements in another 109,703 people. Through this extensive gene mapping they were able to confirm the majority of the gene loci which were already linked to various body measurements, as well as identifying four new gene loci linked to height, and seven loci linked to overweight and obesity. They could also demonstrate a great overlap of gen
|Contact: Erik Ingelsson|