Conserved Y-chromosomal location of TSPY in Bovidae.

We determined the chromosomal location of TSPY, the testis-specific protein, Y-encoded, by fluorescence in situ hybridization (FISH) to chromosome spreads of cattle, goat and sheep. Using a cloned polymerase chain reaction (PCR) product of one bovine TSPY family member, we were able to show a conserved Y chromosomal localization for TSPY in all three species. In contrast to a limited regional distribution of TSPY FISH signals on the chromosome of man, other primates, great apes, goat and sheep, in cattle TSPY-related sequences appear to be spread over most of the Y chromosome. The painting effect observed in this species reflects the higher complexity of the bovine TSPY gene family, being composed not only of a tandemly repeated cluster, but harbouring a large number of different family members dispersed all over the Y chromosome.