Table 1.

HIV-1 protease sequences according to subtype and treatment exposure: datasets used to provide mutation frequency data for the HIVseq program (September 2005)

	PI naive^a			PI experienced
Subtype	Viruses^b	Persons	Citations^c	Viruses^b	Persons	Citations^c
Subtype B	4037	3369	124	5720	3354	104
Non-B subtypes
A	637	621	52	71	59	10
AE	532	524	53	71	64	12
AG	794	791	55	101	83	16
C	993	973	83	276	216	20
D	343	311	55	89	73	23
F	178	173	41	139	129	18
G	261	259	31	185	169	10
Non-B total	3738	3652		932	793

PI, protease inhibitor.

Never received a PI, regardless of their reverse transcriptase inhibitor treatment history.

Total number of virus isolates for which sequences exist in the Stanford HIV RT and Protease Sequence Database (according to subtype and treatment). The number of viruses is higher than the number of patients because some patients have had viruses assessed a multiple time points.

Number of different published references (or unpublished studies associated with GenBank submissions) from which the sequence data were obtained.