Genetics Partially Determines Hep C-Induced Liver Damage
March 13, 2017
Millions of Americans have been infected with the Hepatitis C virus – but only a portion progress to severe liver damage. Clinicians discuss many reasons contributing to Hepatitis C-induced liver damage. New research now includes a genetic variant on the list of liver damage offenders.
There is little an individual can do to change their genetic composition, and thus resist a genetic source of Hepatitis C-induced liver damage. Despite this acknowledgement, uncovering the genetic polymorphism that increases liver damage is the beginning of a new wave of therapeutic research into chronic illness defense. In addition, those who carry this genetic variant are likely to be encouraged to protect their liver from inflammation and begin antiviral therapy promptly.
Hepatitis C and Liver Damage Promoters
A blood-borne virus that can take decades before symptoms emerge, Hepatitis C is an infectious disease that primarily inhabits the liver. Progression of Hepatitis C-inflicted liver damage begins with inflammation of the liver, followed by the death of liver cells. Injured or dead liver cells cause scarring (liver fibrosis). Repeated liver cell damage eventually leads to cirrhosis – the permanent hardening and scarring of liver tissue:
- About 15 to 20 percent of people infected with Hepatitis C fight it off without treatment and suffer no long-term damage to their liver’s health.
- The remaining 80 to 85 percent develop chronic Hepatitis C.
- Approximately 20 percent of those with chronic Hepatitis C experience gradual damage to the liver and go on to develop cirrhosis in 15 to 20 years.
While it is clear that not everyone with Hepatitis C progresses to cirrhosis, healthcare professionals are aware of several factors that promote liver damage.
6 Known Causes of Liver Damage
- Exposure to toxins through ingestion, inhalation, or skin absorption
- Insulin resistance or diabetes
- Co-infection with another hepatitis virus
- Duration of infection
Recently, a large international team of researchers led by The Westmead Institute for Medical Research in Sydney, Australia, found a new cause of liver damage.
The Genetic Variance
According to their study that was published in the September 2016 edition of Nature Communications, researchers analyzed more than 2,000 patients and concluded that a genetic variant puts Hepatitis C patients at greater risk of developing chronic liver disease.
More specifically, they determined that a variant in the MBOAT7 gene is linked to increased liver inflammation and, therefore, associated with scarring. MBOAT7 is a protective enzyme that reduces inflammation – similar to the effect of antioxidants neutralizing free radicals to combat inflammation. Those with the genetic variant have a low expression of MBOAT7, which corresponds with more severe liver inflammation and inflammatory markers in the blood.
Regarding MBOAT7, Professor Jacob George from The Westmead Institute’s Storr Liver Centre commented, “This gene is expressed by many immune cell types and is likely to be critical for the progression of inflammation and fibrosis irrespective of the organ. This could be the key to finding a treatment for a wide range of potentially deadly conditions characterized by tissue scarring that can include diseases of the heart, lungs, and kidney, as well as the liver.”
The findings publicized by The Westmead Institute can be applied in several valuable ways:
- To better understand the role of genetics in disease manifestation.
- Investigate avenues of stimulating or replicating non-variants of MBOAT7 to therapeutically diminish liver inflammation.
- Identify those with Hepatitis C who are most at risk of developing cirrhosis.
Only 20 percent of those with chronic Hepatitis C develop cirrhosis. While there are several promoters of liver damage that could push a person into that 20 percent, a variant of gene MBOAT7 is an additional contributing factor. However, identification of this genetic variant could lead to swift treatment for affected individuals and therapeutic solutions for preventing Hepatitis C-induced liver damage.
http://www.healthcommunities.com/liver-disease/causes.shtml, Liver Disease Causes and Risk Factors, Retrieved October 30, 2016, Remedy Health Media, LLC, 2016.
http://www.healthline.com/health/hepatitis-c/stages-progression#2, The Progression of Hepatitis C: What Are the Stages?, Ann Pietrangelo, Retrieved October 30, 2016, Healthline Media, 2016.
http://www.nature.com/articles/ncomms12757, MBOAT7 rs641738 increases risk of liver inflammation and transition to fibrosis in chronic hepatitis C, K. Thabet, et al, Retrieved October 30, 2016, Nature Communications, September 2016.
https://www.scimex.org/newsfeed/researchers-find-new-genetic-variant-which-puts-hepatitis-c-patients-at-higher-risk-of-liver-damage, Researchers find new genetic variant which puts hepatitis c patients at higher risk of liver damage, Retrieved October 30, 2016, Westmead Institute, 2016.
https://www.thebalance.com/genetic-polymorphism-what-is-it-375594, Genetic Polymorphism: What Is It?, Theresa Phillips, Retrieved October 30, 2016, The Balance, 2016.