Genetics play a significant role in obesity, with researchers from the University of Exeter Medical School discovering that individuals missing a specific blood group due to a genetic variant may be predisposed to obesity or overweight. The SMIM1 gene, responsible for encoding a protein on red blood cells, was found to have an impact on weight. People missing this gene were more likely to be overweight, exhibit altered lipid levels, and have reduced resting energy expenditure. The study, published in the journal Med, used genetics data from around 500,000 individuals in the UK Biobank and other cohorts to identify those with the genetic variant turning off the SMIM1 gene.
The absence of the SMIM1 gene was linked to altered metabolism control, particularly affecting the hypothalamus-pituitary-thyroid axis. This led to reduced energy expenditure, resulting in excess calories being stored as fat. The researchers also found that individuals without the SMIM1 gene function displayed other measures linked to obesity, including high levels of fat in the blood, fat tissue dysfunction, and increased liver enzymes. Lower levels of thyroid hormones were also observed in these individuals, indicating a mild form of hypothyroidism. It was noted that almost 2% of the population in the UK receive thyroid supplementation as a treatment for this condition.
According to Dr. Hans J. Schmidt, director of the Center for Weight Loss and Metabolic Health at Hackensack University Medical Center, obesity often has a genetic cause, with some individuals being predisposed to gaining weight due to genetic variants. The study highlighted a possible link between the loss of function of the SMIM1 gene and excess weight, with the gene playing a role in regulating fat metabolism. Further research is needed to determine the gene’s involvement in metabolism control and whether it is part of a novel pathway or feeds into known pathways that regulate metabolism.
Dr. Mir Ali, medical director of MemorialCare Surgical Weight Loss Center, emphasized the importance of understanding the genetic basis of obesity to improve treatment options. Identifying genetic variants that predispose individuals to obesity could lead to early intervention strategies and the development of targeted medications. By exploring various treatment modalities, researchers may be able to find effective ways to manage obesity in individuals with specific genetic variants. The study underscores the complexity of obesity and the necessity of considering genetic factors in developing personalized treatment approaches for this prevalent health issue.
