| This is a molecular epidemiological study of the occurrence and distribution of M. tuberculosis in selected Asian-Pacific regions and Hawaii.;Population structures of M. tuberculosis isolates in China, Philippines and Hawaii were assessed using IS6110 RFLP (n = 209) fingerprinting and spoligotyping (n = 250) methods. Two novel distinct families, Beijing and Manila families were discovered. These two families are currently dominant in China and the Philippines respectively. Members of Beijing and Manila family of M. tuberculosis isolates constitute 77% of the 51 Hawaiian isolates studied.;Retrospective study of DNA types of M. tuberculosis strains from Beijing was conducted to investigate when the Beijing Family became dominant in the past. Eighty-five lung biopsies prepared between 1956 to 1990 from Beijing were analyzed by spoligotyping. About 90% of positive the biopsy samples demonstrated the Beijing type regardless of sample age, suggesting Beijing genotype has dominated Beijing area at least from late 1950's. This study also showed the spoligotyping method can be successfully used for detection of M. tuberculosis in tissues stored for forty years.;We also compared genetic relatedness of the Beijing family with the W-like MDRTB family, recently detected in New York and found to be spreading in US, with novel and specific multiplex PCR typing method. We found that 80% of the 131 Beijing family strains had the characteristic of "W-like" pattern, regardless of their geographical origin. This indicated that the Beijing family shares genetic similarity with the W-like family. Hypothetically, the establishment of W-like family was due to the movement of the Beijing family to New York City.;A new DR region of the Beijing family strains was cloned and sequenced to improve the discriminative power of the spoligotyping method. Three new spacers, designated a, b, and c were discovered and applied in spoligotyping (n = 152). 94% of the Beijing family stains contained all of the three spacers. None of the non-Beijing strains contain spacer a suggesting that it is Beijing family specific. All of the W and W-like (n = 10) strains were found to possessed all three spacers reinforcing that the W and Beijing families are genetically related. These spacers were previously reported in the DR sequence M. bovis, however, this is the first report of these sequences in M. tuberculosis and their use in Spoliogotyping. |
