title: Nonhomologous synapsis of the XY during early pachynema in In(X)1H male mice.
abstract: It has been previously supposed that meiotic synapsis is restricted to homology during early, but not late pachynema. The synaptic behavior of an inverted X chromosome, In(X)1H as reflected in the synaptonemal complexes of the sex chromosomes has been examined in microspread spermatocytes by electron microscopy and evidence of extensive nonhomologous synapsis between the X and Y during early pachynema has been obtained.
mesh_terms: D000818:Animals; D007446:Chromosome Inversion; D008297:Male; D008540:Meiosis; D051379:Mice; D008817:Mice, Mutant Strains; D008854:Microscopy, Electron; D013573:Synaptonemal Complex; D014960:X Chromosome / Q000648:ultrastructure; D014998:Y Chromosome / Q000648:ultrastructure