A RAPID METHOD OF HAPLOTYPING HFE MUTATIONS AND LINKAGE DISEQUILIBRIUM IN A CAUCASOID POPULATION

Background-HFE mutations are associated with hereditary haemochromatos is. However, a simple method capable of demonstrating the cis/trans ar rangement of alleles is lacking, and linkage disequilibrium between HF E alleles and classic HLA loci is unknown. These are important issues as the pathogenic role of the mutations is not known. Aims-To develop a simple method of genotyping HFE mutations suitable for clinical use in addition to large disease studies, Patients-A total of 330 Caucasoi d cadaveric organ donor controls were examined. Ten individuals previo usly HLA-H genotyped by polymerase chain reaction using restriction fr agment length polymorphism (PCR-RFLP) were also examined to validate t he method. Methods-A simple polymerase chain reaction using sequence s pecific primers (PCR-SSP) capable of haplotyping the mutations was dev eloped. HFE allele and haplotype frequencies and linkage disequilibriu m with eight HLA class I and II loci were examined in the control popu lation, Results-27% and 19.7% of patients were positive for the 63D an d 282Y alleles, respectively. No chromosome carried both 63D and 282Y. Linkage disequilibrium between 282Y and HLA-A03 wars confirmed, but was not straightforward: some A03-associated. alleles (DRB1*15, DQB1* 06), but not all (B07, Cw*0702), were associated with 282Y. Conclusio ns-Linkage disequilibrium data suggest that an HLA-B07 containing hap lotype contains an element affording protection from haemochromatosis and may suggest the timing of the founder 282Y mutation.