Elevated Frequency of HLA Shared‐Haplotypes in Migraine Families

SYNOPSIS Associations between HLA antigens and disease susceptibility have been investigated in several pathological conditions. Previous studies in selected migraine populations did not reveal any association with the HLA system. It is widely accepted that migraine is a disease with familial incidence. The genetic basis of migraine occurrence within 8 families with more than one member affected in two generations was studied. 60 individuals were studied; 33 of them were affected by migraine. HLA-A,B,C,DR typing was performed in 41 individuals using the microlymphocytotoxicity technique of Terasaki. The studied pedigrees failed to identify a particular HLA antigen or HLA haplotype as a genetic marker of migraine. Among the total number of HLA typed individuals entering the study, Sib-pair analysis was done in 20 pairs. The observed frequency of shared-haplotypes differed from the expected frequency: 60% of compared pairs shared one haplotype (expected frequency 50%) and 30% shared two haplotypes (expected frequency 25%).