Relationship between surfactant protein A polymorphisms and allergic rhinitis in a Chinese Han population.

The development of allergic rhinitis is considered to be determined by the interaction between genetic and environmental factors. Surfactant protein A (SP-A), a member of the collectin family of proteins, plays an important role in immune regulation. The purpose of this study was to investigate the association between SP-A polymorphisms and allergic rhinitis. We conducted a case-control association study on a Chinese Han population, comprising 216 adult individuals with AR and 84 healthy controls. A total of 9 single-nucleotide polymorphisms (SNPs) mapped to the SP-A were genotyped using PCR-based molecular identification methods. The frequency of A allele at amino acid 223 in the patient group was significantly higher than that in the control group after correcting for multiple testing (P = 0.006). The 1A(2) allele haplotype in SFTPA2 was associated with decreased risk for allergic rhinitis, after applying Bonferroni corrections (P = 0.003). However, genetic variants of the SFTPA1 genes were not found to be associated with AR. In addition, no significant associations were established between any of the 9 SFTPA gene polymorphisms and the skin-prick test responses (P > 0.05). Further, no association was established between the 9 SNP loci and the levels of total serum immunoglobulin E (IgE) (P > 0.05). These results indicate that the gene polymorphism at the residue 223 in the carbohydrate recognition domain of SFTPA2 may be a genetic marker for the development of AR in the adult Chinese Han population.