Analysis of the polymorphisms in eotaxin gene family and their association with asthma, IgE, and eosinophil

The eotaxin gene family (eotaxin, eotaxin-2, and eotaxin-3) has been implicated in the recruitment of eosinophils, basophiles, and Th2 lymphocytes that is a central aspect of allergic diseases such as asthma. To determine whether the single nucleotide polymorphisms (SNPs) of eotaxin gene family are associated with susceptibility to asthma, we scanned 225 asthma patients and 294 non-asthmatic controls using the direct sequencing method. We further investigated the relationships among each SNP, eosinophils, and serum total IgE levels in asthma patients. Eleven SNPs were identified in the eotaxin gene family. We found that EoB179T>C (P=0.0001), EoB275C>T (P=0.018) of the eotaxin-2 and EoA2497T>G (P=0.003) of the eotaxin-3 were significantly associated with the susceptibility of asthma. Furthermore, our data demonstrated for the first time that EoA2497T>G (P=0.005) is related to serum total IgE level while EoA77C>T (P=0.035) and EoA2497T>G (P=0.033) are related to the peripheral blood eosinophil counts in asthma. Our results suggest that the polymorphisms of the eotaxin gene family are associated with the susceptibility of asthma and Eotaxin-3 might play the critical role for the recruitment of eosinophils and the maintenance of IgE levels.