Summary
Following misdivision of the centromere at meiosis in diploid and triploidFritillaria new telocentric chromosomes are formed whose broken ends rejoin within the centromere. This type of chromosome is delayed at metaphase and anaphase in the pollen-grain mitosis. It may then, either break again at the centromere, or pass without separation to the pole as a new iso-chromosome.
The misdivision and the origin of the iso-chromosome are each likely to be important as affecting the genetic structure of the chromosome and the mechanical properties of the centromere.
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Darlington, C.D. The origin of iso-chromosomes. Journ. of Genetics 39, 351–361 (1940). https://doi.org/10.1007/BF02982848
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DOI: https://doi.org/10.1007/BF02982848