Abstract
In one individual of the triploid hybrid Aloe “Sherman Hoyt” (2n=21) a large supernumerary segment on the end of the long arm of an L2 chromosome was shown to be a reversed duplication formed by the distal breakage of a U-type chromatid bridge at anaphase I in the tetraploid parent. The segment misdivides and is partially or wholly lost during mitotic anaphase at a constant rate. Sectors of tissue lacking the segment do not become established, indicating that its loss is lethal to the daughter cell line after a few mitotic divisions. This constant rate of breakage combined with the elimination of deficient cell lines results in a system which is stable overall.
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Brandham, P.E. Stabilised breakage of a duplicated chromosome segment in Aloe . Chromosoma 51, 269–278 (1975). https://doi.org/10.1007/BF00284820
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DOI: https://doi.org/10.1007/BF00284820