Fatty liver disease happens when triglycerides, a type of fat, build up in the liver. Genetics play a major role in this disease, but until recently, researchers didn’t know which genes were involved. To learn more, researchers at Karolinska Institutet studied genetic data and MRI scans from 71,488 people of European descent in the UK Biobank.
This is the largest study so far in which scientists looked at the whole genome and measured liver fat levels with MRI at the same time. The findings are published in the journal Nature Genetics.
New genes found as possible key factors
The team found 60 separate genetic regions connected to liver fat levels. Out of these, 31 were new discoveries for this trait. The study suggests that common genetic differences explain about 25% of the variation in liver fat among people.
“By almost doubling the number of known genetic regions linked to liver fat, we get a clearer picture of the biological processes behind fatty liver disease,” says Stefano Romeo, professor at the Department of Medicine, Huddinge, Karolinska Institutet.
The researchers also used different methods to find out which genes are likely influenced by these genetic changes. For 48 out of the 60 regions, they could point to genes that probably help cause fatty liver disease.
The team also created a genetic risk scale using many genetic variants. People with the highest genetic risk were more likely to get fatty liver disease and liver cancer than those with the lowest risk. These results suggest that inherited factors that affect fat buildup in the liver may also influence the risk of liver disease later in life.
The researchers note that the study included only people of European descent. Larger studies involving more diverse populations are needed to determine whether the results apply to other groups. Future research should also confirm some of the newly identified genetic regions.