Analysis of gene mutations associated with isoniazid, rifampicin and ethambutol resistance among Mycobacterium tuberculosisisolates from Ethiopia

Table 2 Frequency of gene mutations associated with resistance to isoniazid and rifampicin by GenoType^® MTBDRplus, and to ethambutol by GenoType^® MTBDRsl assays

Anti TB-drugs	Number of resistant isolates	Patterns of gene mutations (wild-type/mutant)	Amino acid Changes	Frequency (n)
Isoniazid	35	katGWT/katGMUT1	Ser315Thr1	33
		inhA WT1/inhA MUT1	C15T	2
Rifampicin	15	rpoB WT8/rpoB MUT3	Ser531Leu	11
		rpoB WT7/rpoB MUT2B	His526Asp	1
		rpoB WT2 &3/NA	Unknown	1
		rpoB WT4/ND	Unknown	1
		rpoB WT6/NA	Unknown	1
Ethambutol	8	embB WT/embB MUT1A	Met306Ile	2
		embB WT/embB MUT1B	Met306Val	1
		embB WT/ND	Unknown	5

n number of isolates, WT wild-type, MUT mutant, ND no mutation detected at mutant probe, NA mutant probe is not available

ISSN: 1471-2334