Is obesity genetic?
A new study from the University of California, Berkeley, reveals that obesity is genetically determined, meaning it’s an inherited trait that can be influenced by diet and exercise.
The study, published online in the journal Nature, was led by UC Berkeley senior study author David Himmelstein, an associate professor of anthropology and a member of the UC Berkeley School of Public Health.
The study’s results could help inform how we understand and treat obesity, and how we can prevent and treat it.
Himmelsteins team looked at more than 8,000 genomes from more than 3,600 people across the globe.
Researchers compared the genes of the people with the most weight-related mutations and those with the least.
The researchers then used these differences to calculate the genetic components of obesity.
The results showed that obesity genes are linked to about three-quarters of the variants associated with obesity, but not all.
For example, some of the obesity-linked genes include genes that help regulate body weight.
For these genes to be expressed in obesity, they need to be present in the body, but there is not enough evidence yet to know if these genes have specific effects on obesity, Himmels team said.
“We now know that obesity genetic variation is linked to at least 50% of the genetic variation associated with fat mass, with obesity being one of the more prevalent obesity-related genetic variants,” said Himmelfeld, a postdoctoral fellow in the Department of Anthropology.
“This is the first study to show that the genes that are expressed in fat cells also play a role in obesity.”
The researchers used a method called microarray analysis to look for the genetic fingerprints of obesity and found a strong correlation between the obesity genetic variant and the genes for leptin, adiponectin and ghrelin.
These are genes that increase the body’s production of these hormones, which are important for regulating appetite, weight loss and energy balance.
In addition, obesity-associated genes affect how fat cells divide and grow.
“Our data clearly shows that obesity-derived genes contribute to body weight, and obesity-induced genes are important to body fat accumulation and development,” said senior author Andrew Miller, a professor of human genetics and biochemistry and biophysics.
“By studying obesity genes in the genomes of people across more than 2,000 populations, our research opens the door to understanding the genetics and behaviors associated with the condition, as well as how obesity can be curbed.”
Himmelfstein said the findings may be useful for identifying potential new genetic targets to treat obesity.
“Understanding the genetics of obesity is important for understanding the mechanisms by which it influences health and the risk of developing obesity,” he said.
“Our results suggest that obesity can also be a genetic risk factor for developing other diseases.
This is important information for the prevention and treatment of obesity.”###