Sun Y-J, Lee A S G, Wong S-Y, Paton N I
Department of Infectious Diseases, Tan Tock Seng Hospital, Singapore.
Clin Microbiol Infect. 2007 Aug;13(8):833-5. doi: 10.1111/j.1469-0691.2007.01752.x. Epub 2007 May 14.
Previous studies have suggested that Mycobacterium tuberculosis kasA G312S and G269S gene mutations may represent sequence polymorphisms of the M. tuberculosis East-African-Indian (EAI) and T families, respectively, rather than relating to isoniazid resistance. The present study examined polymorphisms of these two codons in 98 drug-susceptible M. tuberculosis isolates (68 EAI and 30 T isolates). Twenty-eight isolates belonging to a sub-lineage of the EAI family had the kasA G312S mutation, but none of the 30 T isolates had the G269S mutation. The data suggest that the kasA G312S mutation is not related to isoniazid resistance, but represents a sequence polymorphism in a sub-lineage of the EAI family.
