Researchers from the U.S. and South Africa on Tuesday announced that they have decoded the genome sequence of strains of drug-sensitive tuberculosis, multi-drug resistant TB and extensively drug-resistant TB, which is resistant to the two most potent first-line drugs and some of the available second-line drugs, Reuters reports. Teams from the Microbial Sequencing Center at the Broad Institute of Harvard and MIT and the Nelson Mandela School of Medicine in South Africa collaborated on the study.
For the study, the researchers compared the different strains of TB to identify several mutations that might explain how drug-resistant TB eludes some antibiotic treatments. Initial data showed that the drug-resistant and drug-sensitive microbes differ at a few dozen locations along the four-million-letter DNA code. The code reveals some known drug resistance genes, as well as some additional genes that could enhance understanding of how TB is spread.
Megan Murray, one of the project's lead researchers and a professor at the Harvard School of Public Health, said the results "lay the groundwork for the development of a rapid diagnostic test for TB," which could "enable more rapid and accurate diagnoses and help to prevent the spread of TB -- especially the most virulent strains."
The scientists said they decided to publicize the genome sequence and their initial analysis before publishing the study in a scientific journal to accelerate work on drug-resistant TB worldwide. "It is important that genomic data be made immediately available, particularly to researchers in areas most heavily burdened by disease," Eric Lander of the Broad Institute said. Willem Sturm of the Nelson Mandela School of Medicine said, "Genetic characterization of this strain is essential for developing tools to get this epidemic under control".
Another group of South African scientists in October announced that they had sequenced the genome for one strain of XDR-TB.
Source: Kaiser Family Foundation