Background Transporter antigen peptide gene (TAP) products are involved in antigen processing. These genes, inducible by interferon γ, as well as lymphotoxin α (LT-α), are located in the HLA region. Their involvement in immune response regulation makes them candidate atopy susceptibility genes.
Objective This study investigates a possible association between previously identified polymorphisms within the TAP-1 and LT-α genes and clinically manifested atopic diseases in the Czech population.
Methods Caucasian subjects of Czech nationality (n = 427) were included in our study. We examined 184 healthy controls and 243 patients with histories of atopic asthma, allergic rhinitis and atopic dermatitis or their combinations. We used the amplification refractory mutation system polymerase chain reaction to determine TAP-1 gene polymorphisms. LT-α genotypes were determined by PCR and restriction analysis by NcoI.
Results No significant differences were found in allele or genotype frequencies of the LT-α gene, as well as in polymorphisms for Val→Ile at codon 333 and Gly→Asp at codon 637 in the TAP-1 gene between controls and patients. However, analysis of the concurrence of the double genotypes of the TAP-1 polymorphism at codon 333 and the LT-α genes showed differences between controls and atopic patients (P < 0.02).
Conclusion Several reports have indicated that different HLA products and genes may be risk factors for or protective factors against the development of atopy. We report no association between polymorphisms in the LT-α and TAP-1 genes alone and atopic diseases in the central Europe Caucasian (Czech) population, but there was an interesting interaction between the TAP333 and LT-α polymorphisms.