What does this indicate for how you view primate evolution?
I would agree with Taq, Percy and others that these were examples of gene loss in the ancestors of Chimpanzees since they branched off from a common ancestor with Humans. We can use these pattern of gene loss/gain with other primates to establish phylogenetic relationships and compare this to other features we see in the sequenced genomes to see if they concur.
But this isn't why I posted because Taq and Percy already have this well in hand. What I was looking for was your own interpretation of these patterns. For example, creationists possibly including Durston, tend to separate humans from other primates as separate kinds, possibly going further with ape and monkey kinds. But this example you've raised contradict this depending on however you would define the significance of gene gain/loss.
So how would you describe the relationships of primate species, if any, based on the distribution of shared genes?