Detection of the 10-kD antigen structural gene in mycobacteria by using the polymerase chain reaction.

The structural gene encoding the 10-kD antigen from Mycobacterium tuberculosis was amplified by the polymerase chain reaction. The 297-base-pair (bp) product was detected among 45 strains representing 14 mycobacterial species, but was absent from 11 species related to the mycobacteria. The gene was localized to a approximately 2000-bp SstII restriction fragment of the organisms' chromosomes.