Del(Y)2H

This Y Chromosome (Chr) deletion resulted from asymmetric recombination during male meiosis between the short arm of a Y Chr (Yp) of C57BL/6 origin and an X Chr carrying Tp(Y)1CtSxr-a. Whereas Sry (sex determining region of Chr Y) and 16 other single-copy genes and pseudogenes on Yp appear intact by Southern blot analysis, all except a few copies of the Rbmy (RNA binding motif protein, Y Chr) repeat sequence family, which resides between Sry and the centromere and normally comprises at least 50 copies, have been deleted. Sry transcript levels in genital ridges of 11.5 day post coitus (dpc) XXYDel(Y)2H embryos are detectable at much lower levels than in XY embyos; in contrast, transcripts from Kdm5d, which maps distal to Sry between Zfy1 and Zfy2, are similarly abundant in XYDel(Y)2H and XY 11.5 dpc genital ridges. Conversely, testis-specific Sry transcripts from both the intact Y Chr and YDel(Y)1H are detected in testes of XYYDel(Y)2H male mice by RT-PCR followed by MboI digestion, which distinguishes the M. m. musculus vs. M. m. domesticus Sry variants; cloning of intact RT-PCR products yielded 7/16 M. m. musculus-derived clones. (J:15425, J:29526)