Association between TIM-1 gene polymorphisms and allergic rhinitis in a Han Chinese population.

BACKGROUND TIM-1, a member of the T cell immunoglobulin and mucin (TIM) domain family, is involved in T-cell differentiation and has been implicated in allergic diseases. An association between TIM-1 and allergic rhinitis, however, has not been established. OBJECTIVE To investigate whether TIM-1 gene polymorphisms were associated with allergic rhinitis in a Han Chinese population. METHODS Two TIM-1 promoter single nucleotide polymorphisms (SNPs), -416G>C and -1454G>A, were examined in 185 allergic rhinitis patients of Han Chinese ethnicity using polymerase chain reaction (PCR) and restriction fragment length polymorphism. Additionally, exon 4 insertion/deletion polymorphisms in the TIM-1 gene were analyzed by PCR, polyacrylamide gel electrophoresis, and silver staining. The relationship between gene polymorphisms and serum specific IgE levels in this Han Chinese population was also evaluated. RESULTS We found that the -416G>C and -1454G>A SNPs were associated with allergic rhinitis susceptibility in this Han Chinese population. No statistically significant differences in the distribution of genotype or allele frequencies of 5383_5397ins/del and 5509_5511delCAA in exon 4 were observed. The -416G>C and -1454G>A SNPs were associated with the level of serum IgE specific to house dust mites in patients with allergic rhinitis. CONCLUSIONS These results suggest that TIM-1 gene polymorphisms (-416G>C and -1454G>A) are associated with allergic rhinitis susceptibility in a Han Chinese population.