The fattest gene
The important role of genetic factors in the development of obesity has been demonstrated for a long time. There is data according to which 40-90% of cases of obesity are due to heredity, but each of the couple dozen variants of the "obesity genes" described so far individually increases the probability of gaining excess fat by only a few percent.
A study conducted by American and Israeli scientists from the Mount Sinai Clinic in New York and the Ziv Medical Center in Safed on a mouse model of pathological obesity and with the participation of patients with a family history of this disease showed that the cause of its development may be the loss of functionality of a single gene.
According to one of the leaders of the work, Dr. John Martinetti, the gene identified in family members suffering from pathological obesity turned out to be a fundamental regulator of body weight. This gene exists not only in humans and mice, but also in simpler unicellular organisms, it is so important for the body that nature has preserved it for 700 million years of evolution.
At the first stage of the work, the authors analyzed the genotype of a large Israeli family of Arab origin, whose members suffer from pathological obesity with an autosomal recessive type of inheritance. As a result, they revealed a shortening mutation of the recently identified Cep19 gene encoding the CEP19 protein, which is localized in the centrosome and primary cilia – organelles involved in the process of cell division and perception of external stimuli.
In subsequent experiments, the researchers inactivated the Cep19 gene in mice, which led to an increase in the animals' appetite, reduced energy consumption and impaired fat metabolism. The obvious result of this was the development of pathological obesity and diabetes mellitus.
The authors note that the role of CEP19 protein in maintaining normal body weight is not clear and additional research is needed to identify the mechanisms by which it is involved in appetite regulation, as well as in fat and energy metabolism.
According to Martinetti, obesity has already acquired the status of a global epidemic affecting almost all aspects of human health, ranging from diseases of the cardiovascular system and cancer and ending with most of the causes leading to premature (preventable) death. If we want to overcome this disease, we need to understand the underlying mechanisms.
Article by Shalata et al. Morbid obesity in humans and mice resulting from inactivation of the ciliary protein MO1/CEP19 is published in the American Journal of Human Genetics.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on Elsevier materials:
Scientists identify gene that regulates body weight in humans and mice.
18.12.2013