Table 1.

Relative occurrence of non-conserved cysteine residues in V1, V2 and V4 in HIV-1 subtypes

HIV-1 subtype	na	V1 region				V2 region				V4 region
		Canonicalb	Plus 2 cysteines	Plus 4 cysteines	Total	Normal	2 cysteines	4 cysteines	Total	Canonical	Plus 2 cysteines	Plus 4 cysteines	Total
A	208	98.6	1.4	0	100	99.5	0.5	0	100	100	0	0	100
B	1338	94.4	5.5	0.1	100	99.9	0.1	0.1	100	99.9	0.1	0	100
C	952	94.5	5.1	0.3	100	99.7	0.3	0	100	99.5	0.5	0	100
D	101	99	1.0	0	100	100	0	0	100	100	0	0	100
F	39	100	0.0	0	100	100	0	0	100	100	0	0	100
G	61	73.8	26.2	0	100	100	0	0	100	100	0	0	100
Other	960	96.9	3.1	0	100	99.6	0.4	0	100	89.5	10.5	0	100
Total	3659	95.2	4.7	0.1	100	99.7	0.2	0	100	97.1	2.9	0	100

^aThe number of Env sequences used to calculate the percentage of viruses with canonical or non-conserved cysteine residues per subtype

^bThe percentage of viruses with normal or non-conserved cysteine residue