Background: One of the members of the T cell immunoglobulin (Ig) domain and mucin domain (TIM) gene family, TIM-1, located in the chromosome 5q31-33 region, has been associated with the development of T helper (TH) 2-biased immune responses and may be selectively expressed in TH2 cells. Previous studies have also shown an association between polymorphisms in the TIM-1 gene and asthma or asthma-related phenotypes.

Objective: The aim of the present study was to analyze the association between the TIM-1 polymorphisms -232G>A and 5383_5397 insertion/deletion (ins/del) and susceptibility to asthma in a group of patients from middle China.

Methods: Polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis and PCR-polyacrylamide gel electrophoresis were used to detect -232G>A and 5383_5397 ins/del genotypes in 302 asthmatic children and 206 controls. Serum total IgE was measured by chemiluminescence and specifi c IgE to common aeroallergens by immunoblot analysis.

Results: We found no association between the -232G > A polymorphism and asthma or total serum IgE levels or statistically significant differences between asthma and control subjects in terms of genotype and allele frequency for the 5383_5397 ins/del polymorphism. We did, however, detect a difference in total serum IgE levels for 5383_5397ins/ins genotypes in individuals with atopic asthma (P < .05) in that they had higher IgE levels than those with del/del and del/ins genotypes.

Conclusion: Our results suggest that the 5383_5397 ins/ins genotype in the TIM-1 gene is associated with elevated serum total IgE levels, particularly in individuals with atopic asthma. Further studies are needed to confi rm such an association.

Key words: Asthma. TIM-1. Polymorphism. Serum total immunoglobulin E.