Abstract
X-rays have been used to induce heritable changes in the specific morphology of the lampbrush chromosomes in the newt Pleurodeles waltlii. The karyotype organization of female progeny of irradiated males was studied. Nine out of ten females were found to have chromosomal aberrations. In one of the nine, one of the breaks occurred at the sphere organizer, the sphere being part of the striking morphological features of chromosome IV. On irradiation the normal sphere organizer had been broken into two fragments each of which, when recombined with other chromosome breaks, still forms a sphere. The relationship of these observations to genome redundancy is discussed.
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Lacroix, J.C., Loones, M.T. Fragmentation par les rayons X de l'organisateur d'une différenciation de chromosome en écouvillon (lampbrush), chez Pleurodeles waltlii . Chromosoma 36, 112–118 (1971). https://doi.org/10.1007/BF00326426
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DOI: https://doi.org/10.1007/BF00326426