DIFFERENTIAL-DIAGNOSIS OF HEREDITARY HEMOCHROMATOSIS FROM OTHER LIVERDISORDERS BY GENETIC-ANALYSIS - GENE MUTATION ANALYSIS OF PATIENTS PREVIOUSLY DIAGNOSED WITH HEMOCHROMATOSIS BY LIVER-BIOPSY

Background.-Hereditary hemochromatosis, a common autosomal recessive t rait caused by mutations in the HLA-H gene, is often diagnosed by the pathologist at the time of histologic examination. Unfortunately, hist ologic parameters alone do not differentiate between hereditary hemoch romatosis and other causes of iron overload. We performed a retrospect ive study to determine the frequency of familial hemochromatosis in pa tients diagnosed with he mochromatosis by abnormal liver histology. Me thods and Results.-DNA was isolated from paraffin-embedded tissue sect ions from 15 patients and used in a polymerase chain reaction-based as say in which we tested for the C282Y and H63D mutations. We found that in this group of patients, 5 (33%) were homozygous for the common C28 2Y genetic mutation, 3 (20%) were heterozygous, and 7 (47%) were norma l. Conclusions.-Our study shows that the molecular assay is the gold s tandard for the diagnosis of hereditary hemochromatosis. The case stud y also illustrates that a definitive diagnosis of familial hemochromat osis has significant counseling implications allowing for accurate fam ily studies.