Reduced phenotypic expression in genetic hemochromatosis with time: role of exposure to nongenetic modifiers
This article by Yves Deugnier and colleagues Reduced phenotypic expression in genetic hemochromatosis with time: role of exposure to nongenetic modifiers. Deugnier Y, Morcet J, Lainé F, Hamdi-Roze H, Bollard AS, Guyader D, Moirand R, Bardou-Jacquet E. J Hepatol. 2018 Sep 20. pii: S0168-8278(18)32383-3. doi: 10.1016/j.jhep.2018.09.009. [Epub ahead of print]
provides evidence for something that many of us suspected for some time. Hereditary hemochromatosis is no longer the devastating disease that we had learned about in medical school (cirrhosis, liver cancer, bronze diabetes etc.). Clearly several factors influence this trend. More and more cases are picked up by screening so milder phenotypes are included in the diagnosis. However, the 30 year trends in markers of severity started to change even before screening was widely available, and the age at diagnosis has not decreased. Alcohol, originally thought to cause the disease, then discounted when the genetic basis of the disease was identified, has in the end turned out to be a major cofactor. Heavy alcohol consumption is decreasing in the regions where the disease is common. Adding to this, decreased smoking and increased obesity appear to contribute to a milder phenotype, likely by increasing plasma hepcidin levels.
These changes have important implications for IBIS which was founded by physicians and scientists focused on the pathogenesis and treatment of hereditary hemochromatosis. Is it time to declare victory and move on to other topics, like iron-loading anemias, the role of iron in promoting infections, iron as a modifier of inflammation, and many other problems of iron biology?