HLA-DQA1 AND HLA-DQB1 HAPLOTYPES IN ABORTED FETUSES AND COUPLES WITH RECURRENT SPONTANEOUS-ABORTION

HLA haplotypes may be associated with spontaneous abortion through a v ariety of mechanisms, including maternal hyporesponsiveness to fetal a lloantigens, maternal autoimmunity, and HLA-linked t-locus homologues. HLA-DQA1 and HLA-DQB1 haplotypes were determined in 37 couples with a history of recurrent spontaneous abortion (RSAB), 40 of their abortus es, and 20 fertile control couples. The distribution of haplotype freq uencies did not differ between control subjects and RSAB wives, RSAB h usbands, or abortuses. The frequency of the HLA-DRS-Iinked haplotype, DQA1501/DQB1*301, which was considered a marker for immune hyporespon siveness, did not differ between RSAB wives and control subjects (P = 0.353). The frequency of the autoimmune-associated HLA-DR3-linked hapl otype, DQA10501/DQB1*0201, did not differ significantly between RSAB wives and control subjects (P = 0.103). The frequency of the DQA10201 /DQB10201 haplotype in RSAB husbands was greater than the 95th percen tile confidence limit of the frequency of this haplotype in control su bjects. Among seven RSAB husbands who were heterozygous for this haplo type and did not share a DQA10201 allele with his wife, the haplotype was transmitted to 6 of 7 abortuses (3.5 expected). Although the smal l size of this sample precludes drawing conclusions regarding HLA tran smission biases in RSAB couples, these data have generated a specific hypothesis regarding the DQA10201/DQB1*0201 haplotype that can be inv estigated in future studies.