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- CAD, coronary artery disease
- HFE, haemochromatosis
- LDL, low density lipoprotein
- MI, myocardial infarction
- PCR, polymerase chain reaction
- PTCA, percutaneous transluminal coronary angioplasty
Hereditary haemochromatosis is the most common genetic disorder in white people. Its prevalence exceeds the combined incidence of cystic fibrosis, muscular dystrophia, and phenylketonuria.1 The faulty haemochromatosis gene (HFE) (OMIM 235200) was discovered in 19962 and is localised on the short arm of chromosome 6. A single mutation, 845A (c845A; GenBank U60319 OMIM 235200.0001) in the HFE gene results in the substitution of tyrosine for cysteine at amino acid 282 in the corresponding HFE protein and is referred to as the C282Y mutation. About 0.3% of C282Y homozygotes and 10% of heterozygotes are found in white populations.3–6 A higher prevalence in Ireland, Wales, and Brittany, and in white Australians compared to the south of Europe suggests a Celtic origin for the C282Y mutation.7 A second mutation in the HFE gene (c187G; H63D (GenBank U60319 OMIM 235200.0002)) contributes only in combination with C282Y to iron overload (compound heterozygosity).
Of patients with clinically identified haemochromatosis 80%– 90% are homozygous for the C282Y mutation.8 The disease is characterised by increased iron deposition in the liver, heart, pancreas, and other organs, leading to liver cirrhosis, heart failure owing to cardiomyopathy, and diabetes mellitus. On the other hand, the penetrance of the C282Y mutation is variable; homozygotes without evidence of iron overload have been described.9 Heterozygotes are in general healthy but have slightly increased concentrations of serum ferritin, serum iron, and increased iron saturation of serum transferrin.10 In combination with established liver disease, heterozygotes show a worse disease course,11,12 but there are also conflicting results.13
An association between atherosclerotic disease and iron deposition has been suggested for several years. In vitro findings suggest a role for excess iron in atherosclerosis. Iron promotes the oxidation of low density lipoprotein (LDL).14 The ferritin gene is …