Maintaining a healthy bodyweight is all about balancing the calories we eat with the amount that we burn as energy, but new research has found a new genetic cause of obesity. Those with a genetic variant that disables the SMIM1 gene find it harder to reach this balance, because they expend less energy while resting. It means that some people really do face a bigger challenge when battling the bulge.
This new discovery was uncovered by a team of international researchers, led by the University of Exeter in England. To make their findings, scientists looked at the genetics of almost half a million people in the UK Biobank database and 100,000 blood donors. They discovered that those with a genetic variant that switches off the SMIM1 gene had a higher bodyweight averaging out at +4.6 kilograms for women and +2.4 kilograms in males. Experts think that the condition could affect at least 300,000 people around the world.
“SMIM1 was only discovered a decade ago, as a long-sought blood group protein on red blood cells, but its other function has remained unknown until now. It’s very exciting to find that it has a more general role in human metabolism,” explained the studies co-author, Jill Storry.
Lead author, Mattia Frontini said: “Obesity rates have nearly tripled in the past 50 years, and by 2030, more than one billion individuals worldwide are projected to be obese. The associated diseases and complications create significant economic burden on healthcare systems. Obesity is due to an imbalance between energy intake and expenditure, often a complex interplay of lifestyle, environmental, and genetic factors.
In a small minority of people, obesity is caused by genetic variants. When this is the case, new treatments can sometimes be found to benefit these people – and we’re now hoping to run a clinical trial to find out whether widely-available drug for thyroid supplementation may be beneficial in treating obesity in people who lack SMIM1.”
The study noted that those who were lacking in SMIM1 suffered from higher levels of fat in their blood, tissue dysfunction, increased liver enzymes, and lower thyroid hormone levels. Scientists now hope do develop a treatment that can reverse the condition.