Abstract
A competitive polymerase chain reaction (cPCR) assay for the quantitative evaluation of Mycobacterium tuberculosis growth was developed based on co-amplification of genomic DNA and a modified DNA fragment derived from a well-conserved region of the 16S rRNA gene. There was a good correlation between the number of DNA copies in the sample, indicated by competitive PCR, and the number of colony forming units determined by conventional culture methods.