I have a question here:
Deletion of a gene (just say gene A) has been found in human population
at a high frequency. Deletion of its orthologous gene was also found in
chimpanzees. The genomic sequences of human and chimp are very similar
and these two deletions look just like each other. Can we say the
deletion was inherited from the common ancestor of human and chimp or
did it happen twice independently in the two species? Is there a way to
tell the difference?