While certain lifestyle factors play a role in obesity, researchers have realized that genetics can also be an influencer. For instance, a study presented earlier this year found children may inherit obesity from their parents. A study published in February 2023 linked 21 genes related to Alzheimer’s disease to obesity. Now, scientists from the University of Exeter Medical School in England have found that people missing a specific blood group due to a genetic variant may be genetically predisposed to obesity or being overweight.
Researchers believe these people missing the SMIM1 gene may be treated using an already available drug for thyroid dysfunction. The study was recently published in the journal Med.Using both genetic and blood sample data, Frontini and his team found that people with a loss of SMIM1 gene function were more likely to be overweight.
Researchers found that people with two faulty copies of the (SMIM1) gene — about 1 in 5,000 — are heavier than those who don’t [have it]. They have altered lipids in their blood, and they use less energy given the same caloric intake. The excess is going to be stored as fat.
The absence of SMIM1 causes a mild form of hypothyroidism which results in reduced resting energy expenditure. In other words, these people use less energy given the same caloric intake — meal — which results in the excess being stored as fat. This is a common occurrence, almost 2% of the population in the U.K. receive thyroid supplementation, which is an effective and cheap treatment. Some people easily gain weight and others eat whatever they want and never gain a pound. There are many genes involved in metabolism and fat storage but in some rare cases, a single genetic variant leads to obesity.
This study shows there is evidence suggesting a link between a loss of function of the SMIM1 gene and excess weight. SMIM1 codes for a protein involved in regulating fat metabolism. In patients with no gene function, reduced energy expenditure leads to weight gain. The researchers incidentally found an association with obesity. The best next step would be to engage other researchers, studying other genetic traits, to see if there is an association between other genes and weight — both overweight and those not able to gain weight.
