The interaction of the polymorphisms in transporter of antigen peptides (TAP) and lymphotoxin alpha (LT-alpha) genes and atopic diseases in the Czechpopulation

Background Transporter antigen peptide gene (TAP) products are involved in antigen processing. These genes, inducible by interferon gamma, as well as lymphotoxin alpha (LT-alpha), arc located in the HLA region. Their involvem ent 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-alpha genes and clinicall y 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 combina tions. We used the amplification refractory mutation system polymerase chai n reaction to determine TAP-1 gene polymorphisms. LT-alpha genotypes were d etermined by PCR and restriction analysis by NcoI. Results No significant differences were found in allele or genotype frequen cies of the LT-alpha gene, as well as in polymorphisms for Val-->Ile at cod on 333 and Gly-->Asp at codon 637 in the TAP-1 gene between controls and pa tients. However, analysis of the concurrence of the double genotypes of the TAP-1 polymorphism at codon 333 and the LT-alpha genes showed differences between controls and atopic patients (P < 0.02). Conclusion Several reports have indicated that different HLA products and g enes may be risk factors for or protective factors against the development of atopy. We report no association between polymorphisms in the LT-<alpha> and TAP-1 genes alone and atopic diseases in the central Europe Caucasian ( Czech) population, but there was an interesting interaction between the TAP 333 and LT-alpha polymorphisms.