Phylogenetic relationships in the APOL gene family in primates. A phylogenetic tree was created from the large-exon sequences of each APOL gene, which includes ∼70%–85% of each coding sequence. Pseudogenes are shown in parentheses, and probabilities of individual clades are shown at central topological junctions. Within individual APOL gene clades, sequences cluster according to the established primate phylogeny (Purvis 1995). The tree shows numerous duplications of APOL genes: APOL2.1 is the result of a duplication that occurred after the divergence of APOL1 and APOL2; APOL7 is the result of a duplication that occurred after the divergence of APOL1/L2 and APOL3/L4; and, depending on the location of the tree root, which is unknown, the APOL1/L2 and APOL3/L4 clades may themselves be products of a duplication that occurred early in primate evolution.
