Researchers Epigenetic Causes of Obesity Decrypted

Epigenetic variant involved in the development of obesity
The cause of overweight and obesity is often in the genes. In addition to the genetic material, so-called epigenetic variants, ie changes in the environment of the genome, are to be considered as possible causes of obesity, according to a recent study at the Charité - Universitätsmedizin Berlin. A particular epigenetic variant leads to a significantly increased risk of developing obesity, the researchers report.

In their study, the scientists were able to prove that not only genetic factors but also so-called epigenetic variants influence the risk of obesity. "Thus, an epigenetic variant on the Proopiomelanocortin gene (POMC gene), which plays a special role in the regulation of body weight, leading to an increased individual risk of overweight in the course of life," said the Berlin Charité. The researchers published their results in the journal "Cell Metabolism".

A particular epigenetic variant is associated with a significantly increased risk of obesity, according to recent study results. (Image: vladimirfloyd / fotolia.com)

Regulation of body weight genetically influenced
In previous studies with identical twins, there was already evidence that a high genetic content is involved in the regulation of body weight, the researchers report. However, only a small proportion of overweight cases could be explained by the previously discovered genetic variants. "Therefore, we investigated the question of whether apart from genetic epigenetic changes could also play a role in the regulation of body weight. Peter Kühnen from the Institute for Experimental Pediatric Endocrinology at the Berlin Charité.

POMC gene with higher methylation intensity
The so-called epigenetics describes variants that can regulate the function of a gene without the affected gene sequence itself being altered. "Probably the most stable epigenetic change is the so-called DNA methylation, the coupling of a chemical compound, a methyl group, to the genetic material," explain the scientists of the Berlin Charité. The extent to which the epigenetic variants influence the regulation of body weight has so far remained largely unexplored. In the current study, the researchers were able to show that "obese children and adults had a higher percentage of methylation than a normal person at a certain point of the POMC gene," says endocrinologist Dr. med. Bold of the results.

Influence of the fathers on DNA methylation
Furthermore, according to the researchers, the same methylation variant could be detected in the POMC neurons in the brain of deceased, overweight persons. Also, the epigenetic change after birth was found in blood cells and it remained unchanged during the first years of life, according to the Charité. In addition, the scientists were able to observe a paternal influence on this POMC DNA methylation in children, the Charité continues.

A risk factor among many
Although the epigenetic variant is not the main cause of obesity, it is only one potential factor of many. However, the change in the gene that is important for the regulation of body weight seems to increase the risk of overweight significantly, the researchers explain. Further studies are now to clarify how this epigenetic variant of the gene is produced and how, for example, the influence of the father on the degree of DNA methylation of the child can be explained. (Fp)