Types | Gene | Age of Onset | Iron Burden | Liver | Bones and Joints | Heart | Pituitary |
Type 1 | HFE | ≈40 - 60 | +/+++ | ++ | ++ | + | + |
Type 2A | HJV | ≈15 | +++ | +++ | ++ | +++ | ++++ |
Type 2B | HAMP | ≈15 | +++ | +++ | ++ | +++ | ++++ |
Type 3 | TFR2 | ≈30 | +++ | +++ | ++ | + | ++ |
Type 4A | SLC40A1 | Any | +/+++ | ? | − | − | − |
Type 4B | SLC40A1 | Any | +/+++ | ++ | − | − | − |