Is all genetic (hereditary) hemochromatosis HLA-associated.

1. GH in Australia is significantly associated with the HLA-A3 antigen, which is the only independent marker for the disease (B7 in linkage disequilibrium with A3). 2. The haplotype A3, B7, DR2 is the only one with increased prevalence in this disease, presumably due to its being the predominant haplotype among early immigrants. 3. Exceptions to HLA association in GH are rare and can be explained by: (1) incorrect HLA serotyping, (2) chromosomal recombination, or (3) rare homozygous-homozygous mating. 4. These data are consistent with GH being due to a mutant gene or genes in close proximity to HLA-A. 5. Heavy alcohol ingestion does not lead to expression of hemochromatosis in heterozygous subjects.