British and French scientists say variants of a single gene may hardwire some people for obesity, according to a new study published in the journal Nature.
A team of scientists led by Philippe Froguel of Imperial College London studied whether variants of the gene PCSK1, combined with other genetic factors, would lead to more complex and widespread forms of obesity.
When they compared the genomes of 13,000 obese individuals of European ancestry to those of a normal control group, the researchers found three mutations in the gene that were far more common among those coping with excess weight, Agence France-Presse reported.
The same variants were also linked to increased risk of childhood obesity, the study found.
PCSK1 produces the enzyme proconvertase 1, which helps convert inactive forms of the hormones insulin and glucagon into active forms.
The two hormones are involved in the metabolism of sugar and carbohydrates, and help control the appetite.
"Nearly 25 percent of the population has a different form of the enzyme that is apparently a little bit more active,'' Froguel told AFP.
Froguel's team has identified several other genes that also play a role in obesity. Researchers believe that identification of these genes will help them come up with new and better ways to treat the disease.