Accelerated evolution of Protocadherin11X/Y: a candidate gene-pair for cerebral asymmetry and language. by Williams, N, Close, J, Giouzeli, M, Crow, T

“…We re-date the duplicative translocation to 6 million years ago, that is, close to the chimpanzee-hominid bifurcation. Sequence comparisons with the chimpanzee, bonobo, gorilla, and orangutan indicate that in contrast to earlier purifying selection there has been accelerated change in the Protocadherin11X ectodomain as well as the Protocadherin11Y sequence in the hominid lineage since the duplication. …”

ProtocadherinX/Y, a candidate gene-pair for schizophrenia and schizoaffective disorder: A DHPLC investigation of genomic sequence by Giouzeli, M, Williams, N, Lonie, L, DeLisi, L, Crow, T

“…Low sequence variation suggests selective pressure against sequence change in modern humans in contrast to the structural chromosomal and sequence changes including fixed X-Y differences that occurred in this region earlier in hominid evolution. Our findings exclude sequence variation in PCDHX/Y as relevant to the aetiology of psychosis. …”