TABLE 3.

Frequency of rpoB mutations among Beijing family and non-Beijing family rifampin-resistant M. tuberculosis isolates

Position of mutation	No. (%) of isolates with substitution
	Beijing (n = 50)	Non-Beijing (n = 16)
Gln-513	4 (8.0)
514-Phe ins.a		1 (6.3)
Asp-516	9 (18.0)	2 (12.5)
His-526	6 (12.0)	1 (6.3)
Ser-531	26 (52.0)	8 (50.0)
Leu-533		2 (12.5)
None	5 (10.0)	2 (12.5)

^aPhenylalanine insertion.