TABLE 1.

Summary of hemochromatosis phenotypes with their corresponding genes and clinical manifestations^a.

Types		Main clinical manifestations	Inheritance
Type 1	HFE *	Late onset, >30 years old, mild to severe hepatomegaly, elevated aminotransferase levels, arthralgia, arthritis	Recessive
Type 2	Hemojuvelin (HJV)/ Hepcidin (HAMP)	Early onset, <30 years old, severe cardiomyopathy, arrhythmia, diabetes, hypogonadism	Recessive
Type 3	TFR2	Late onset, >30 years old, mild to severe hepatomegaly, elevated aminotransferase levels	Recessive
Type 4	Ferroportin (SLC40A1)	Late onset, >40 years old, mild hepatomegaly, elevated aminotransferase levels, arthralgia, arthritis	Dominant

^aPietrangelo, 2004; Brissot and de Bels, 2006; Andrews, 2008; Fix and Kowdley, 2008; Powell et al., 2016.

*Variation in this gene including C282Y, H63D, and S65C are associated with increasing risk of neurodegenerative disorders particularly Parkinson’s disease.