Researchers at the University of California, San Diego School of Medicine say that hepatic fibrosis, which involves scarring of the liver that can result in dysfunction and, in severe cases, cirrhosis and cancer, may be as much a consequence of genetics as environmental factors. The findings are published online in the journal Gastroenterology.
"The most common known causes of hepatic fibrosis have been viral hepatitis C infections, alcohol abuse, poor diet and obesity and nonalcoholic steatohepatitis or NASH, which resembles alcoholic liver disease but occurs in people who drink little or no alcohol," said first author Rohit Loomba, MD, associate professor of clinical medicine in the Division of Gastroenterology.
"We found, however, that hepatic fibrosis and steatosis (infiltration of liver cells with fat) are strong genetic traits. At around 50 percent heritability, they're more genetic than body mass index."
Loomba and colleagues performed a cross-sectional analysis of 60 pairs of twins residing in Southern California. Forty-two pairs were monozygotic or identical, meaning they developed from a single fertilized egg that split to form two embryos. Eighteen were dizygotic or fraternal, developing from two different eggs, each fertilized by separate sperm cells.
Using two advanced magnetic resonance imaging techniques that quantify fat content in the liver and liver stiffness (a measure of fibrosis), the researchers found that 26 of the 120 participants had nonalcoholic fatty liver disease (NAFLD), which can be a precursor to development of more serious conditions. Hepatic steatosis and liver fibrosis correlated strongly with monozygotic twins, but not with dizygotic pairs.
"This evidence that hepatic steatosis and hepatic fibrosis are heritable traits has major implications," said Loomba. "It means that we can now look for the relevant genes as potential therapeutic targets."
Loomba said the research team plans to expand their research to include the role of the microbiome - the collective genomes of the microorganisms that reside within and on humans, and which also indicates a degree of heritability.
Hepatic steatosis and fibrosis are among the hottest areas in research and medicine at the moment, according to Loomba, with more than a dozen clinical trials currently underway. NAFLD, which is characterized by hepatic steatosis, is the most common cause of chronic liver disease in the United States, affecting 80 to 100 million Americans, with 18 million believed to have the more serious NASH.
Co-authors include Nicholas Schork, and Karen E. Nelson, J. Craig Venter Institute; Chi-Hua Chen, Ricki Bettencourt, Ana Bhatt, Brandon Ang, Phirum Nguyen, Carolyn Hernandez, Lisa Richards, Joanie Salotti, Steven Lin, Ekihiro Seki, Claude B. Sirlin, and David A. Brenner, all at UC San Diego.
Funding support for this research came, in part, from the American Gastroenterological Association Foundation, a T. Franklin Williams Scholarship Award, Atlantic Philanthropies, Inc., the John A. Hartford Foundation, the Association of Specialty Professors and the American Gastroenterological Association (grant K23-DK090303).
Scott LaFee | EurekAlert!
Bioinspired nanoscale drug delivery method developed by WSU, PNNL researchers
10.01.2019 | Washington State University
How herpesviruses shape the immune system
09.01.2019 | German Center for Infection Research
World first experiments on sensor that may revolutionise everything from medical devices to unmanned vehicles
The new sensor - capable of detecting vibrations of living cells - may revolutionise everything from medical devices to unmanned vehicles.
Dead and alive at the same time? Researchers at the Max Planck Institute of Quantum Optics have implemented Erwin Schrödinger’s paradoxical gedanken experiment employing an entangled atom-light state.
In 1935 Erwin Schrödinger formulated a thought experiment designed to capture the paradoxical nature of quantum physics. The crucial element of this gedanken...
Cellulose obtained from wood has amazing material properties. Empa researchers are now equipping the biodegradable material with additional functionalities to produce implants for cartilage diseases using 3D printing.
It all starts with an ear. Empa researcher Michael Hausmann removes the object shaped like a human ear from the 3D printer and explains:
The phenomenon of so-called superlubricity is known, but so far the explanation at the atomic level has been missing: for example, how does extremely low friction occur in bearings? Researchers from the Fraunhofer Institutes IWM and IWS jointly deciphered a universal mechanism of superlubricity for certain diamond-like carbon layers in combination with organic lubricants. Based on this knowledge, it is now possible to formulate design rules for supra lubricating layer-lubricant combinations. The results are presented in an article in Nature Communications, volume 10.
One of the most important prerequisites for sustainable and environmentally friendly mobility is minimizing friction. Research and industry have been dedicated...
Just in time for Christmas, a Mars-analogue mission in Morocco, coordinated by the Robotics Innovation Center of the German Research Center for Artificial Intelligence (DFKI) as part of the SRC project FACILITATORS, has been successfully completed. SRC, the Strategic Research Cluster on Space Robotics Technologies, is a program of the European Union to support research and development in space technologies. From mid-November to mid-December 2018, a team of more than 30 scientists from 11 countries tested technologies for future exploration of Mars and Moon in the desert of the Maghreb state.
Close to the border with Algeria, the Erfoud region in Morocco – known to tourists for its impressive sand dunes – offered ideal conditions for the four-week...
16.01.2019 | Event News
14.01.2019 | Event News
12.12.2018 | Event News
17.01.2019 | Physics and Astronomy
17.01.2019 | Materials Sciences
17.01.2019 | Information Technology