Analysis of hsp70 gene polymorphism in allergic asthma

Background: Allergic asthma is a multifactorial and probably multigenic inf lammatory disease of the upper airways, and has been associated with the HL A class II alleles DR4 and DR7. Here we investigated possible associations with other polymorphic susceptibility/resistance genes located within the m ajor histocompatibility complex, i.e., the genes coding the major 70-kDa he at-shock proteins (HSP; Hsp70) hsp70-1, hsp70-2, and hsp70-HOM, whose produ cts are overexpressed in the bronchi of asthmatic patients. Methods: Genomic DNA was extracted from peripheral blood lymphocytes or buc cal epithelial cells of 48 patients with allergic asthma and 31 selected no natopic control subjects, in whom we previously reported a strong associati on of atopy with DR4/DR7 alleles. Results: No evidence was found for an independent role of hsp70 gene polymo rphism in susceptibility to allergic asthma. However, hsp70 alleles might b e involved in extended haplotypes of HLA markers. Conclusions: Our data suggest that Hsp70 overexpression in asthma results f rom complex interactions between environmental exposures and genetic backgr ound rather than from specific genetic Variations in hsp70 genes.