IS6110-restriction fragment length polymorphism and spoligotyping analysis of Mycobacterium tuberculosis clinical isolates for investigating epidemiologic distribution in Korea

The Beijing family of Mycobacterium tuberculosis has been emerging in the world.However, there are few nationwide data of genotypic distribution in Korea. This study aimed to identify the genotypic diversity of clinical isolates ofM. tuberculosis and to demonstrate the population of Beijing family in Korea. We collected 96 clinical M.tuberculosis isolates from 11 university hospitals nationwide in Korea from 2008 to 2009. We observed 24 clusters in IS6110-RFLP analysis and 19 patterns in spoligotyping. Seventy-five isolates were confirmed to be Beijing family. Two isolates of the K strain and 12 isolates of the K family strain were also found. We found that drug resistance phenotypes were more strongly associated with Beijing family than non-Beijing family (P=0.003). This study gives an overview ofthe distribution of genotypes of M. tuberculosis in Korea. These findings indicate thatwe have to pay more attention to control of M. tuberculosis strains associated with theBeijing family.