Certain genetic variants that may be responsible for making people fat have been identified by researchers from University of Alabama at Birmingham.
Maria De Luca, who led the study of 228 women, says that natural variation in the human LAMA5 gene may be a key determinant of weight.
She and her colleagues first identified candidate genes using different strains of fruit fly Drosophila melanogaster, and later tested three common variations in the human LAMA5 gene.
This led to the identification of two gene variants that were associated with body shape - one in women of European American descent and the other affecting women of American African descent.
"We found one variant to be associated with weight and lean mass in both ethnic groups. This variant was also associated with height, total fat mass and HDL-cholesterol, but only in European American women. A different variant was associated with triglyceride levels and HDL-cholesterol in African American women," Maria said.
As to whether the use of flies in a study of human obesity may prove beneficial, Maria said: "Insects store fat like mammals do, as lipid droplets accumulated in the fat body, the functional equivalent of both mammalian liver and white adipose tissue."
She added: "Drosophila share many components of fat biosynthesis, degradation and regulation with humans, including many of those implicated in diabetes and obesity."
The study has been published in the open access journal BMC Genetics.