Background: Single-nucleotide polymorphism (SNP: rs2289276, rs3806933) of thymic stromal lymphopoietin (TSLP) has been reported to have susceptibility to bronchial asthma (Harada et al.AJRCMB, 2011). Association of polymorphisms of TSLP gene with atopic status, pulmonary function (PF) and airway hyperresponsiveness (AHR) in asthmatics with or without smoking has not been precisely elucidated. Objectives: We analyzed the relationship between SNP of TSLP (rs2289276, rs3806933) and atopic status, PF and AHR in asthmatics. Methods: We recruited 280 asthmatics to the current study who visited Iwate Medical University Hospital from 2006 to 2011. Subjects were genotyped using rs2289276 and rs3806933 by 7500 Fast Real-Time PCR System, (Applied Biosystems USA). PF was evaluated by spirometer. AHR to methacholine was measured by Astograph; Jupitor 21 (Chest, Japan). AHR was expressed as D min. This study was approved by the ethics committee of Iwate Medical University. Results: Genotyping of rs3806933 showed that 165 C/C, 115 C/T and 19 T/T. Atopic status between C/C and C/T+T/T was significantly different (Chi-square analysis). Neither PF or D min of the 3 genotypes was not significantly different. However there was a significant difference of FEV1 %predicted between C/C and C/T+T/T in never smoker with asthma (p=0.015, Mann-Whitney U-test) Conclusion: SNP (rs3806933) in TSLP was associated with atopic status and FEV1 %predicted in the never smoker of the current asthmatic population, suggesting that TSLP was involved in immune response induced by allergens and modification of immune reaction by smoking.
