Comparative mapping of SRY in the great apes.

Cytogenetic studies of the primate Y chromosomes have suggested that extensive rearrangements have occurred during evolution of the great apes. We have used in situ hybridization to define these rearrangements at the molecular level. pHU-14, a probe including sequences from the sex determining gene SRY, hybridizes close to the early replicating pseudoautosomal segment in a telomeric or subtelomeric position of the Y chromosomes of all great apes. The low copy repeat detected by the probe Fr35-II is obviously included in Y chromosomal rearrangements during hominid evolution. These results, combined with previous studies, suggest that the Y chromosome in great apes has a conserved region including the pseudoautosomal region and the testis-determining region. The rest of the Y chromosome has undergone several rearrangements in the different great apes.