Two single nucleotide polymorphisms in TSLP gene are associated with asthma susceptibility in Chinese Han population

Background: Asthma is a chronic inflammatory disease of the airway that is mediated by T-helper 2(TH2) cells. Thymic stromal lymphopoietin (TSLP) can aggravate asthmatic lung inflammation by activating dendritic cells (DCs) to promote TH2 differentiation. TSLP promoter polymorphisms are associated with susceptibility to bronchial asthma in Japanese population. We sought to determine whether single nucleotide polymorphisms (SNPs) in TSLP gene are associated with asthma in Chinese Han population. Objective: To analyze the polymorphism of the two SNPs Rs2289276 and Rs2289278 in TSLP gene and to evaluate the association between the two SNPs and asthma susceptibility in Chinese Han population by using case-control study. Methods: five hundred and thirty one asthmatic patients and 540 age-sex matched normal controls were collected and DNA were extracted from peripheral blood, then the genotypes of SNPs Rs2289276 and Rs2289278 in TSLP gene were detected with polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP), genotype and allele frequencies were calculated and analyzed with Chi-square test. Results: Frequencies of CC/CT/TT genotypes at Rs2289276 site were 0.4706/0.4392/0.0902 in the asthmatic patients and 0.5604/0.3800/0.0595 in the healthy controls. Frequencies of CC/CG/GG genotypes at Rs2289278 site were 0.6502/0.2966/0.0532 in the asthmatic patients and 0.5795/0.3428/0.0777 in the healthy controls. The genotype and allele frequencies of the two SNPs in asthma patients were significantly different from those in the healthy controls. Rs2289278 C allele was correlated with decreased FEV1: FVC (P <= .05). Conclusions: TSLP variants are significantly associated with bronchial asthma. TSLP might be a new therapeutic target molecule for asthma.