Researchers at Sweden’s Karolinska Institutet have identified 31 previously unknown genetic regions linked to liver fat levels, offering powerful new insight into the causes of fatty liver disease and the risk of developing liver cancer later in life.
The landmark study analysed genetic data and MRI scans from 71,488 people of European descent in the UK Biobank. Published in the journal Nature Genetics, it is the largest study to date to examine the entire genome alongside MRI-based measurements of liver fat.
Fatty liver disease occurs when triglycerides, a type of fat, accumulate in the liver. Although scientists have long known that genetics play an important role in the condition, they had not fully understood which genes contribute to its development. The new research identified 60 genetic regions associated with liver fat levels in total, of which 31 had never been linked to the trait before, and pinpointed likely disease-related genes in 48 of those regions.
Lead researcher Professor Stefano Romeo of Karolinska Institutet’s Department of Medicine in Huddinge said that by almost doubling the number of known genetic regions linked to liver fat, scientists now have a far clearer picture of the biological processes driving fatty liver disease.
The findings also carry clinical promise. Using multiple analytical methods, the team developed a genetic risk score based on numerous genetic variants, and found that people with the highest scores were more likely to develop fatty liver disease and liver cancer than those with the lowest scores. The researchers estimated that common genetic differences account for around 25 percent of the variation in liver fat levels between individuals.
The study does come with caveats. It included only people of European descent, so further research in more diverse populations is needed to determine whether the findings apply to other groups, and some of the newly identified genetic regions still require independent confirmation.
Even so, the discovery opens the door to better screening tools and future drug targets. If inherited factors shaping liver fat accumulation also shape the risk of serious liver disease, genetic testing could one day help identify at-risk patients years before symptoms appear.
