Evolutionary history of IL22RA2 gene. A phylogenetic diagram of seven primates selected in this study. The numbers next to branches on the tree show the approximated divergence time from the last common ancestor in million-year time units (MYA). The arrow indicates the estimated point of emergence of the target exon caused by the LTR mutation from AT to GT making the canonical donor site.
Piriyapongsa et al. BMC Genomics 2007 8:291 doi:10.1186/1471-2164-8-291