TABLE 1.

Summary of Env origins and traits

Isolate	Origin	Transmission	Clade	Coreceptor	Infection	Tier	V1/V2 length	No. of predicted N-linked glycans per protomere	GenBank accession number	PubMed identifier
BG505.c2	NBTa	MTCTb	A	R5	Acute	2	17/46	24	ABA61516.1	16378985
MG505.e1	NBT	M-Fc	A	R5	Chronic	NCf	17/46	27	ABA61511.1	16378985
BF520.e3	NBT	MTCT	A	R5	Acute	2	17/41	28	KX168096	27345369
BS208.b1	NBT	MTCT	A	R5	Acute	2	13/42	22	KX364401	16378985
PVO.4	Italy	M-Md	B	R5	Acute	2/3	29/48	32	AAW64259.1	16051804
KNH1144	Discarded blood units from Kenyatta National Hospital	Unknown	A	R5	Chronic	NC	28/44	27	AAN03143.1	12218394

^aNBT, Nairobi Breast Feeding Clinical Trial.

^bMTCT, mother-to-child-transmission.

^cM-F, male-to-female transmission.

^dM-M, male-to-male transmission.

^ePredicted using Los Alamos HIV sequence database N-GlycoSite software.

^fNC, not characterized.