Molecular features of the TSPY gene of gibbons and Old World monkeys

Restriction pattern, chromosome localization and the sequence of the testis-specific gene, TSPY, were investigated in the white-handed gibbon, agile gibbon, siamang, hamadryas baboon and Japanese monkey. Southern blot analysis showed the TSPY gene to be male specific in the primates used and disclosed variability of restriction pattern in gibbons. Fluorescence in situ hybridization demonstrated that the probe ppTSPY2372, biotinylated using polymerase chain reaction, is located as a slight signal in the proximal long arm of the Y chromosome of the white-handed gibbon, hamadryas baboon and Japanese monkey and in the middle long arm of the Y chromosome of the siamang, while a faint signal and an intense signal were detected in the proximal long arm of the Y chromosome of the aglle gibbon. These findings allow us to speculate that the gibbons might have evolved some structural differentiation in the TSPY gene. The first introns of the TSPY genes were sequenced and compared. One hundred thirty-seven of 606 sites were found to be variable, and 10 deletions/insertions were noted among these gibbons, two species of Old World monkeys and human. Sequence similarity ranged from 81.7% between humans and hamadryas baboons to 98.7% between Japanese monkeys and hamadryas baboons. These sequences may be of great use in future studies for resolving the phylogeny of gibbons and Old World monkeys.