SIMIAN Y-CHROMOSOMES - SPECIES-SPECIFIC REARRANGEMENTS OF DAZ, RBM, AND TSPY VERSUS CONTIGUITY OF PAR AND SRY

The three human male specific expressed gene families DAZ, RBM, and TS PY are known to be repetitively clustered in the Y-specific region of the human Y Chromosome (Chr). RBM and TSPY are Y-specifically conserve d in simians, whereas DAZ cannot be detected on the Y chromosomes of N ew World monkeys. The proximity of SRY to the pseudoautosomal region ( PAR) is highly conserved and thus most effectively stabilizes the pseu doautosomal boundary on the Y (PABY) in simians. In contrast, the non- recombining part of the Y Chrs, including DAZ, RBM, and TSPY, was expo sed to species-specific amplifications, diversifications, and rearrang ements. Evolutionary fast fixation of any of these variations was poss ible as long as they did not interfere with male fertility.