Table 1.

Temporal appearance of high frequency mutations during disease progression in vivo

	Mutation
	R1	S55L	D135G	Q138R	R127K*	G110D*	V105A*	S55P*	R143H*	G134D	V112A†
Group‡	B	B	A	A	A	A	A	A	A	A	A
Days p.i.§	Inoc	Inoc	Inoc	Inoc	118	201	754	754	754	Inoc	35

^*Mutations most frequently observed in the background of D135G/Q138R.

^†Mutation most frequently observed in the background of G134D.

^‡Group assignment of high frequency mutations is based on previous phylogenetic and cluster analyses of Rev populations observed in vivo (Baccam et al., 2003). Variants in Group A have overall higher Rev activity than variants in Group B.

^§The first day post-inoculation each high frequency Rev mutation was observed at greater than 50 % frequency in the sampled population.