title: Recombination between the mouse Y chromosome short arm and an additional Y short arm-derived chromosomal segment attached distal to the X chromosome PAR.
abstract: In a male mouse, meiosis markers of processed DNA double strand breaks (DSBs) such as DMC1 and RAD51 are regularly seen in the non-PAR region of the X chromosome; these disappear late in prophase prior to entry into the first meiotic metaphase. Marker evidence for DSBs occurring in the non-PAR region of the Y chromosome is limited. Nevertheless, historically it has been documented that recombination can occur within the mouse Y short arm (Yp) when an additional Yp segment is attached distal to the X and/or the Y pseudoautosomal region (PAR). A number of recombinants identified among offsprings involved unequal exchanges involving repeated DNA segments; however, equal exchanges will have frequently been missed because of the paucity of markers to differentiate between the two Yp segments. Here, we discuss this historical data and present extensive additional data obtained for two mouse models with Yp additions to the X PAR. PCR genotyping enabled identification of a wider range of potential recombinants; the proportions of Yp exchanges identified among the recombinants were 9.7 and 22.4 %. The frequency of these exchanges suggests that the Yp segment attached to the X PAR is subject to the elevated level of recombinational DSBs that characterizes the PAR.
authors.affiliation: Department of Stem Cell Biology and Developmental Genetics, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, UK. Fanny.Decarpentrie@crick.ac.uk.|Mill Hill Laboratory, The Francis Crick Institute, London, NW7 1AA, UK. Fanny.Decarpentrie@crick.ac.uk.
authors.forename: Fanny
authors.initials: F
authors.lastname: Decarpentrie
authors.affiliation: Department of Stem Cell Biology and Developmental Genetics, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, UK.|Mill Hill Laboratory, The Francis Crick Institute, London, NW7 1AA, UK.
authors.forename: Obah A
authors.initials: OA
authors.lastname: Ojarikre
authors.affiliation: Inserm UMR_S 910, Aix Marseille Université, 13005, Marseille, France.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mitchell
authors.affiliation: Department of Stem Cell Biology and Developmental Genetics, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, NW7 1AA, UK.|Mill Hill Laboratory, The Francis Crick Institute, London, NW7 1AA, UK.
authors.forename: Paul S
authors.initials: PS
authors.lastname: Burgoyne
mesh_terms: D000818:Animals; D021461:Animals, Outbred Strains; D005260:Female; D008297:Male; D008540:Meiosis; D051379:Mice / Q000235:genetics*; D000071439:Pseudoautosomal Regions / Q000235:genetics*; D011995:Recombination, Genetic; D014960:X Chromosome / Q000235:genetics*; D014998:Y Chromosome / Q000235:genetics*
keywords: Meiosis; Mouse; Recombination; Short arm (Yp); Spo11; Y-chromosome