Chromosomal evolution in the vlei rat, Otomys irroratus (Muridae: Otomyinae): a compound chromosomal rearrangement separates two major cytogenetic groups
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Published on: March 15, 2018
R V Rambau1, F F Elder, T J Robinson
1Department of Zoology, Stellenbosch University, Stellenbosch , South Africa.
Abstract:
G- and C-banding delimits two cytogenetic groups within the vlei rat, Otomys irroratus. One has a diploid number of 2n = 24, resulting from a centric fusion of chromosomes 7 and 12 of the O. irroratus standard coupled with a tandem fusion to chromosome 8. The second has a diploid number of 2n = 28, lacks the compound chromosome, and appears to have a far wider geographic distribution within South Africa. Additionally, the two groups differ through the presence of cytotype-specific heterozygous centric fusions and one to three B chromosomes which appear as floating polymorphisms in the 2n = 28 complex.
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