Distribution of HFE C282Y and H63D mutations in the Balearic Islands (NE Spain).

The HFE gene contains two main missense mutations: C282Y and H63D. Individuals with these mutations carry a risk of developing hereditary haemochromatosis (HH). The common form of this disease is due to homozygosity for the C282Y mutation. Population studies have shown the variation of the prevalence of these mutations in different countries and ethnic groups. The purposes of this current study were to determine the prevalence of the C282Y and H63D mutations in the Balearic Islands and the genotypic characterization of patients diagnosed with HH, as well as those with iron overload and liver diseases. A total of 1330 Balearic chromosomes were analyzed. The results showed that the populations of the Balearic Islands were not homogeneous. No C282Y carriers were observed in a group of descendants of Majorcan Jews (Chuetas) and the frequency was very low in Minorca (1.2%) in comparison with the other islands of Majorca (4.7%) and Ibiza (6.5%). The carrier frequency of the H63D mutation was similar in the three islands and very high (43.1%) in the descendants of Majorcan Jews. The study of patients was carried out in 129 individuals. The homozygous C282Y genotype was the principal one involved in hereditary haemochromatosis (90%), whereas the other HH patients were C282Y/H63D compound heterozygous and H63D homozygous.