In 1996 the gene and mutation responsible for hereditary haemochromatosis (HHC) were identified.1 In the short time since then, this discovery has greatly changed our knowledge of HHC and has given us new methods for its diagnosis and strategies for its management, together with the potential for greater insight into normal and abnormal iron metabolism.

HHC is a common disorder of iron metabolism which results in iron accumulation in parenchymal cells of the liver, heart, and certain endocrine organs, with eventual organ damage such as cirrhosis. It affects 1 in 300 people of northern European descent with a carrier rate of about 10%. Without treatment, the disease is often fatal, but if treatment starts before tissue injury occurs, patients have a normal life expectancy. An early diagnosis of affected individuals is therefore crucial.

The gene identified by Feder et al 1(“HLA-H” but now defined as HFE2) lies approximately 5 Mb telomeric to HLA-A and shows similarity with MHC class I genes. A single mutation is associated with HHC in 65 to 100% of cases. The mutation is a G to A transition at nucleotide 845 and results in the substitution of a cysteine with tyrosine at position …