A novel Y231del mutation of HFE in hereditary haemochromatosis provides in vivo evidence that the Huh-7 is a human haemochromatotic cell line

Abstract

Hereditary haemochromatosis (HH), which is mainly associated with a C282Y polymorphism in HFE, is common among Caucasians of north European descent, but is very rare among Asians. Herein, we report a 43-year-old Japanese man who was diagnosed as having HH. A laboratory examination revealed an elevated serum iron level (280 μg/dl), hyperferritinemia (1698 ng/ml) and a low serum level of hepcidin-25 (4.0 ng/ml). Abdominal magnetic resonance imaging revealed findings suggestive of iron accumulation in the liver and pancreas. HFE gene sequencing in the patient revealed a novel homozygous TAC nucleotide deletion (c. 691_693del) responsible for the loss of a tyrosine at position 231 (p. Y231del) of the HFE protein. This homozygous Y231del mutation was recently found in the Huh-7 hepatoma cell line and was shown to prevent the translocation of HFE to the cell surface. This clinical case provides in vivo evidence suggesting that Huh-7 is undoubtedly a human haemochromatotic cell line and, as such, is a valuable tool for investigating the pathogenesis of HFE-related HH in humans.