Frekvensen af haemokromatoseassocierede mutationer i haemokromatosegenet i den danske befolkning. ØsterbroundersØgelsen

INTRODUCTION: Hereditary haemochromatosis is an autosomal recessive condition characterised by systemic iron overload. In Northern Europe, 85-90% of patients with haemochromatosis are homozygous for the C282Y mutation in the HFE gene. In the present study, we determined the prevalence of the haemochromatosis-associated mutations, C282Y and H63D, in the Danish general population.

MATERIAL AND METHODS: We genotyped 9174 individuals from a random sample of the Danish general population (The Copenhagen City Heart Study), stratified by gender and age in 10-year age groups, for the presence of C282Y and H63D.

RESULTS: In The Copenhagen City Heart Study, 0.25% (95% confidence interval: 0.16-0.38%) were homozygous for C282Y, 1.4% (1.2-1.7%) were compound heterozygous for C282Y/H63D, and 9.2% (8.6-9.9%) were heterozygous for C282Y alone. Accordingly, the allele frequencies of C282Y and H63D in the Danish population were 5.6% (5.3-5.9%) and 12.7% (12.2-13.2%). All in all, more than 10% of the Danish population are either homozygous or heterozygous for C282Y, whereas about 24% are either homozygous or heterozygous for H63D.

CONCLUSION: A prevalence of 0.25% homozygotes and > 10% heterozygotes for C282Y makes hereditary haemochromatosis the potentially most common inherited disorder in Denmark. However, in new studies from USA of the association between genotype and disease in unselected populations the penetrance is very low. On this background, population screening for the presence of these mutations is not advisable.