title: Molecular cytogenetic analysis and centromeric satellite organization of a novel 8;11 translocation in sheep: a possible intermediate in biarmed chromosome evolution.
abstract: During analysis of genome organization in sheep (Ovis aries, 2n = 54, XY/XX), we found a novel chromosomal translocation in an animal expected to be normal, adding to the six 'centric fusions' previously reported. The translocation was identified as t(8;11) by G-banding and was shown to be centric, involving whole chromosome arms by chromosome painting with probes for Chromosomes (Chrs) 8 and 11. Satellite I and a newly isolated satellite II clone was used to characterize the centromeric regions of both the novel and the three pairs of evolutionarily derived biarmed chromosomes. The novel t(8;11) showed satellite I proximal on both arms with satellite II covering the centromere, while the evolutionarily derived fusion leading to Chrs 2 and 3 showed the opposite configuration, not obviously derived by a simple fusion. Chr 1 has lost the satellite I hybridization patterns. The novel t(8;11) provides strong evidence for an intermediate step in evolution of the biarmed chromosomes in sheep.
authors.affiliation: Department of Genetics and Biotechnology, Centre of Genetics and Biotechnology/ICETA-UTAD, University of Trás-os-Montes and Alto Douro, P-5000-911Vila Real, Portugal. rchaves@utad.pt
authors.forename: Raquel
authors.initials: R
authors.lastname: Chaves
authors.forename: Filomena
authors.initials: F
authors.lastname: Adega
authors.forename: Johannes
authors.initials: J
authors.lastname: Wienberg
authors.forename: Henrique
authors.initials: H
authors.lastname: Guedes-Pinto
authors.forename: John S
authors.initials: JS
authors.lastname: Heslop-Harrison
mesh_terms: D000818:Animals; D002871:Chromosome Banding; D002874:Chromosome Mapping; D002875:Chromosomes / Q000648:ultrastructure*; D019143:Evolution, Molecular; D017403:In Situ Hybridization; D007621:Karyotyping; D008677:Metaphase; D018895:Microsatellite Repeats; D008856:Microscopy, Fluorescence; D009693:Nucleic Acid Hybridization; D012756:Sheep; D014178:Translocation, Genetic