Lack of association between the microsatellite polymorphism in intron 2 of human Toll‐like receptor 2 gene and bronchiectasis among Koreans

BACKGROUND AND OBJECTIVE: The genetic factors for the development of bronchiectasis are not well understood in most patients. The aim of this study was to elucidate the possible association between bronchiectasis and guanine-thymine (GT) repeat polymorphism in intron 2 of the human Toll-like receptor 2 (TLR2), which has a crucial role in adaptive as well as innate immunity. METHODS: A total of 194 patients with bronchiectasis and the same number of age- and gender-matched healthy blood donors were prospectively enrolled. The numbers of GT repeats were determined by PCR and gene scans. For further analysis, the alleles were classified into three subclasses: 12-16 GT repeats, short alleles (S allele); 17-22 repeats, medium-length alleles (M allele); and 23-27 repeats, long alleles (L allele). RESULTS: The overall distribution of alleles was not different between patient and control groups (P = 0.71). In addition, the frequencies of genotypes including short alleles were not different between patient and control groups (P = 0.92). Extent of bronchiectasis (P = 0.92) and bacterial colonization (P = 0.48) were not associated with any subclass genotype. CONCLUSIONS: Alleles and genotype including the shorter GT repeats in intron 2 of the TLR2, were not associated with the development, extent and bacterial colonization of bronchiectasis in Koreans.