IRX3 – the main regulator of "obesity genes"?

Geneticists have found a new candidate for the role of the "main" gene of obesity

RIA NewsAmerican geneticists have found out that the IRX3 gene is the main regulator of the size of the fat layer in the body of mice and humans and that controlling its work can help create means to lose excess weight or get rid of anorexia, according to a brief report published in the journal Nature (Smemo et al., Obesity-associated variants within FTO form long-range functional connections with IRX3; much more about this work can be read in the press release of The University of Chicago Medicine: IRX3 is likely the ‘fat gene’ - VM).

"The data we have obtained clearly indicate that IRX3 controls body weight and determines the composition of its tissues. This gene is a "switch" that controls the operation of several genetic "programs" in cells at once. We are interested in how it changes them and what causes these changes, which will help us create drugs that correct the work of IRX3," said Marcelo Nobrega from the University of Chicago (USA).

Nobrega and his colleagues studied the work of another alleged "obesity gene" – FTO, which was discovered during a comparison of the genomes of about 40 thousand Europeans in 2009. In the following years, scientists tried to uncover the mechanism of action of this gene on the example of mice, which could not be done due to differences in the work of FTO in humans and these rodents.

So, unlike humans, mutations in FTO did not lead to changes in fat mass, but in total weight in mice. The authors of the article approached this problem in a different way – they studied the structure of the genetic "neighborhoods" of FTO and analyzed how they were associated with obesity.

Scientists found that the main "regulator" of obesity was not FTO, but its "neighbor" – the IRX3 gene, whose work was influenced by mutations in the "junk" part of FTO. Having discovered a new candidate for the role of the main cause of overweight problems, the authors of the article checked whether this was the case by damaging IRX3 in the genomes of several mice.

The experiment confirmed the suspicions of geneticists – mice with a broken version of IRX3 were twice as light as rodents from the control group who followed a high-calorie diet with a high proportion of fats. It is not yet clear what processes IRX3 controls, but biologists hope that its further study will help solve the problem of obesity.

Portal "Eternal youth" http://vechnayamolodost.ru13.03.2014