MOLECULAR ANALYSIS OF HLA-H GENE-MUTATIONS IN NEW-ZEALAND PATIENTS WITH HEMOCHROMATOSIS

Aim. To determine the frequency of HLA-H gene mutations in New Zealand patients with haemochromatosis. Methods. The Cys282Tyr and His63Asp m utations in the HLA-H gene were analysed by polymerase chain reaction, restriction enzyme digestion and electrophoresis in two separate pati ent groups. The first was a group of 20 Christchurch patients with a d efinite clinical diagnosis of haemochromatosis. The second group consi sted of 33 patients, with a provisional diagnosis of haemochromatosis, attending Dunedin Hospital for therapeutic venesection. Results. All 20 Christchurch patients and 25 of the 33 (76%) Dunedin patients were homozygous for the Cys282Tyr mutation. After review of the clinical da ta, histology and response to venesection a diagnosis of haemochromato sis could be confidently excluded in six of the remaining eight patien ts. Despite atypical features, a diagnosis of haemochromatosis could n ot be excluded in the final two patients, one of whom was a compound h eterozygote for the two mutations. Conclusions. Homozygosity for the C ys282Tyr mutation is closely associated with haemochromatosis in New Z ealand patients. Molecular analysis of the HLA-H gene is indicated in the assessment of patients with iron overload including those currentl y being treated by venesection.