▎WuXi AppTec content team editor
What effects obesity has on health has a lot to do with where fat accumulates in the body. The same is fat, than thick legs or large hips, thick waist, long belly meat needs more attention. Many studies have found that fat accumulation in the waist and abdomen and around internal organs is associated with increased insulin resistance and inflammation, and the risk of cardiovascular disease, kidney failure, stroke and other diseases is also higher.
Therefore, to pay attention to the problem of obesity, you can not only focus on weight, but also need to pay attention to the indicator of "waist-hip ratio", because this indicator can measure belly fat well. Specifically, divide your waist circumference by your hip circumference to get a ratio of more than 0.99 for men and 0.9 for women, which is something to pay attention to.
Image source: 123RF
However, where fat tends to accumulate is controlled to some extent by genes. Some people get fat as soon as they get fat, and losing weight is the most difficult to reduce the abdomen, which is related to genetics.
Recently, in a paper published in Nature Genetics, scientists identified dozens of genes that are related to the "talent" that makes fat more likely to grow in the waist and abdomen. They also noticed that one of these genes was strongly associated with a woman's waist-hip ratio. Therefore, based on a person's genetic variants in these genes, it is possible to design interventions that are more targeted to prevent the many health problems that obesity may cause.
To find these genes, researchers at the University of Chicago, the University of Minnesota and others collaborated to analyze the genetic data of hundreds of people. Taking the waist-hip ratio of these people as the main indicator and referring to their body mass index (BMI), the research team identified 91 genes from the genome that were associated with the waist-hip ratio in women and 42 genes with the waist-hip ratio in men. The differences between related genes in males and females may be related to differences in body size, fat distribution, and metabolic function between different sexes.
The researchers focused on one of these genes, called SNX10, which is most strongly associated with higher waist-to-hip ratios in women. Although men also express this gene, it does not affect the waist-hip ratio in men.
Image source: 123RF
Experiments in human fat cells have shown that the SNX10 gene controls the differentiation and maturation of fat cells. When the researchers knocked out SNX10 from fat precursor cells, the fat precursor cells were unable to accumulate lipids and develop into mature fat cells.
The results of animal experiments showed that female mice lacking the SNX10 gene in fat cells did not produce excess fat even if they were fed a high-fat diet. In contrast, female mice with normal expression of SNX10, as well as all male mice on a high-fat diet (with or without SNX10), were more likely to eat fat.
Similar to SNX10, the multiple genes found this time mainly help regulate the fat distribution of women, and most of the different variants do not have sequence changes in the region encoding the protein, but change in the non-coding region, so it may play a role in the differentiation of fat cells by regulating gene expression.
The researchers also further verified the effects of relevant genes on obesity and belly fat in the population through the database of the UK Biobank. Taking SNX10 as an example, some genetic variants increase the expression of related genes in fat cells, and the analysis showed that women with these genetic variants not only had a relatively high waist-hip ratio, but also higher blood cholesterol and triglyceride levels, both of which are typical indicators of cardiovascular risk.
"Among the hundreds of genes associated with obesity, fat accumulation, we have identified a gene that has a high probability of making obesity-related diseases more likely." Professor Marcelo Nobrega, one of the study's lead authors, noted, "Moreover, this gene mainly works on women. Next, the research team says they will delve into the regulatory mechanisms of SNX10 and other similar genes to figure out how they affect metabolism, ultimately hoping to lead to new ways to improve obesity.
Resources:
[2] Genes that may predict complications from obesity differ between the sexes. Retrieved Feb. 17, 2023 from https://medicalxpress.com/news/2023-02-genes-complications-obesity-differ-sexes.html