Background: HLA class II genetic polymorphism has been variably implicated in susceptibility to specific immune responsiveness to house dust mite (HDM) allergens, and may also influence the development of atopy.
Objective: In order to assess accurately the influence of HLA alleles in the atopic immune response, we typed 22 families selected from 131 previously obtained randomly selected families (i.e. without regard to atopy or asthma), chosen on the basis of two or more members having skin prick reactivity to HDM.
Methods: Each individual was fully typed for HLA-DRB1, DQA1, DQB1 and DPB1 class II alleles using a combination of sequence-specific oligonucleotide probes (SSOP) and sequence-specific primer (SSP) polymerase chain reaction (PCR) typing and direct sequencing.
Results: Using appropriate statistical tests, no significant allelic associations were found between any DRB1, DQB1 or DPB1 alleles and atopy or skin prick reactivity to Dermataphagoides pteronyssinus (Der p) or D. farinae (Der f). However, positive associations were found between DQA1*0301 and skin prick reactivity to Der f (P = 0.009) and atopy (P = 0.027). Sib-pair analysis revealed no significant sharing of alleles between affected sib pairs for any of the phenotypes studied.
Conclusion: These results fail to confirm a previously reported association between the DRB1*04 and 07 haplotypes and atopy, and suggest that HLA class II restriction does not play a major role in the development of the IgE response to domestic house dust mite allergens in the British population.