Table 1.

Positions in HIV-1 pol where the direct mutational pathway from consensus (wild type) to a resistance-associated mutation (RAM) is shorter in some non-B subtypes than in subtype B.

Position in pol	ART class	RAM residuea	Shortest mutational pathway
			Subtype B	Non-B subtypeb
PR V82	PI	S T	GTC→TCC GTC→AGC	G, CRF14: ATC→AGC G, CRF14: ATC→ACC
RT D67	NRTI	N	GAC→AAC	CRF04: AAC
RT K70	NRTI	G R	AAA→GGA AAA→AGA	CRF04: AGA→GGA CRF04: AGA
RT V106	NNRTI	M	GTA→ATG	C: GTG→ATG
RT V179	NNRTI	E	GTT→GAG	G, CRF02, CRF14: GTG→GAG
RT T215	NRTI	F Y	ACC→TTC ACC→TAC	CRF04: TCC→TTC CRF04: TCC→TAC
IN E157	INI	Q	GAA→CAA	CRF03: CAA

NOTE. Consensus sequences based on the reference sets from Los Alamos National Laboratory (http://www.hiv.lanl.gov). ART, antiretroviral therapy; CRF, circulating recombinant form; IN, integrase; INI, integrase inhibitor; NNRTI, nonnucleoside reverse-transcriptase inhibitor; NRTI, nucleoside reverse-transcriptase inhibitor; PI, protease inhibitor; PR, protease coding region; RT, reverse-transcriptase coding region.

^aSingle-letter amino acid code.

^bNon-B subtypes are underlined.