Genetics and Obesity: New Discoveries in Mexico

Genomic research has revealed that obesity results from a complex interaction between genetics, environment, and biological processes, opening new perspectives for understanding this disease from the standpoint of precision medicine. Scientific studies conducted at the National Institute of Genomic Medicine (INMEGEN) have provided new evidence to understand the biological mechanisms that influence the development of obesity in the Mexican population. The studies identified that hundreds of genetic variants are involved in the susceptibility to this disease, although these variants do not determine on their own that a person will develop obesity, since their effect depends on the interaction with environmental factors and biological processes. This was explained by Dr. Lorena Orozco, an emeritus researcher and leader of the Laboratory of Immunogenomics and Metabolic Diseases of the institute, who pointed out that obesity must be understood as the result of a complex interaction between genetics, environment, and the body's regulatory mechanisms. Genetic variants and susceptibility to obesity According to studies in which researchers from INMEGEN participated, multiple genetic variants that influence metabolism and the regulation of energy balance have been identified in the Mexican population. These variants affect the function of genes involved in physiological processes such as: energy storage, appetite regulation, and inflammatory responses of the body. The researcher explained that these variants do not cause obesity directly, but they do modify how the body processes energy, which can increase susceptibility to developing the disease when they interact with certain environments. Evolutionary origin of the so-called "thrifty genes" As explained by Lorena Orozco, some of these genetic variants originated over thousands of years as a result of evolutionary processes. During long periods of food scarcity, indigenous peoples developed genetic adaptations that favored energy conservation, a mechanism known as "thrifty genes." In the current context, these same variants can interact with an environment characterized by the availability of ultra-processed, high-calorie foods, sedentary lifestyles, and stress, conditions that increase the likelihood of developing obesity. The role of epigenomics in metabolic regulation Another relevant line of research developed by INMEGEN has focused on epigenomics, a discipline that studies how environmental factors can modify the activation or silencing of genes without altering the DNA sequence. The specialist explained that factors such as diet, physical activity, or stress can generate epigenetic changes that influence metabolism, particularly in processes such as: chronic low-grade inflammation and hormonal regulation. These mechanisms affect the functioning of key organs for metabolism, such as adipose tissue, the liver, and the pancreas. Gut microbiome and energy metabolism INMEGEN's research has also explored the role of the gut microbiome, that is, the set of microorganisms that inhabit the digestive system. This microbial ecosystem plays important roles in: metabolism regulation, inflammatory response, and satiety signals. When an alteration occurs in this system — a process known as dysbiosis — changes are generated in energy processing and inflammatory mechanisms, which can favor weight gain. Genetic susceptibility and obesogenic environment The researcher emphasized that the presence of genetic variants associated with obesity does not mean that a person is destined to develop the disease. Genetic variants increase the risk, but they require interaction with an obesogenic environment for obesity to manifest. This means that environmental factors and lifestyles continue to play a fundamental role in the development of the disease. Genomic medicine to understand obesity in Mexico Finally, the researcher highlighted that the scientific projects developed by INMEGEN seek to explain why the Mexican population has a greater vulnerability to obesity, as well as to generate solutions based on genomic medicine. These investigations allow for a better understanding of the biological mechanisms of the disease and to advance towards more precise prevention and care strategies for the Mexican population.