South African geneticists have decoded the genome of an extensively drug-resistant tuberculosis strain. Whether this will lead to better treatments is unknown, but it should help scientists develop better diagnostics -- and that could be just as beneficial.
The sequencing took just one week from start to finish and showed that the XDR-TB strain, taken from a South African patient in KwaZulu Natal, the site of a vicious outbreak last August, differs only slightly from regular tuberculosis. That only a few mutations should produce such a killer is frightening. However, if it's also possible to rapidly genotype each emergent strain and develop quick-and-dirty tests for a few key genes or proteins, then doctors should be able to detect XDR-TB much sooner than they now can.
In the fight against XDR-TB, early diagnosis may be even more important than treatment: at present, determining whether a person's TB is resistant to both first- and second-line drugs is a time-consuming procedure, and often involves treating the patient and seeing what happens. If they're already resistant to those drugs, that just makes the strain stronger.
South African scientists crack drug-resistant TB code [SciDev.net]
Few Mutations Divide Some Drug-Resistant TB Strains [Science]
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