Researchers at Mayo Clinic's Center for Individualized Medicine have made a groundbreaking discovery: a rare genetic variant that can directly cause metabolic dysfunction-associated steatotic liver disease, formerly known as nonalcoholic fatty liver disease. It is one of the most common diseases in the world. ⁠ ⁠ Until now, scientists believed the disease resulted from a combination of genetic and environmental factors. This study, published in Hepatology, reveals that in some cases, a single in