Abstract
Baboons (genus
) and geladas (
) are now generally recognized as close phylogenetic relatives, though morphologically quite distinct and generally classified in separate genera. Primate specific
retrotransposons are well-established genomic markers for the study of phylogenetic and population genetic relationships. We previously reported a computational reconstruction of
phylogeny using large-scale whole genome sequence (WGS) analysis of
insertion polymorphisms. Recently, high coverage WGS was generated for
The objective of this study was to apply the high-throughput "poly-Detect" method to computationally determine the number of
insertion polymorphisms shared by
and
, and vice versa, by each individual
species and
. Secondly, we performed locus-specific polymerase chain reaction (PCR) assays on a diverse DNA panel to complement the computational data.
We identified 27,700
insertions from
WGS that were also present among six
species, with nearly half (12,956) remaining unfixed among 12
individuals. Similarly, each of the six
species had species-indicative
insertions that were also present in
. In general,
shared more insertion polymorphisms with
than did any of the other five
species. PCR-based genotype data provided additional support for the computational findings.
Our discovery that several thousand
insertion polymorphisms are shared by
and
baboons suggests a much more permeable reproductive barrier between the two genera then previously suspected. Their intertwined evolution likely involves a long history of admixture, gene flow and incomplete lineage sorting.