Ml phylogenetic tree of HIV-1 CRFs20/23/24_BG pol (?1000 pb) sequences circulating in Cuba (n?=?118) and Spain (n?=?7).Branches are colored according to the origin of each sequence, as indicated at the legend (top left). The circular brackets highlight the distribution of the three CRFs_BG clades. The tree was rooted using HIV-1 subtype G reference sequences (black branches). Key nodes with aLRT support values >0.80 (*) and ?0.90 (**) are indicated. The branch lengths are drawn to scale with the bar at the bottom indicating nucleotide substitutions per site.