Radiation-induced nondisjunction in mouse oocytes

• Published in: Nature (London) 1974-08, Vol.250 (5467), p.601-602
• Main Authors: UCHIDA, IRENE A., LEE, C. P. VIOLA
• Format: Article
• Language: English
• Subjects: Animals; Cesium Isotopes; Chromosome Aberrations; Dose-Response Relationship, Radiation; Female; Humanities and Social Sciences; Hybridization, Genetic; letter; Meiosis - radiation effects; Mice; Mice, Inbred C3H; Mice, Inbred ICR; multidisciplinary; Ovum - radiation effects; Radiation Effects; Radioisotopes; Science; Science (multidisciplinary)
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/250601a0

BECAUSE chromosomal trisomy is found with relatively high frequencies in congenital malformations and spontaneous abortions in man, the aetiology of abnormal segregation is a pressing problem. One possible factor is exposure of women to diagnostic X rays 1–8 . Experiments with Drosophila melanogaster indicate that nondisjunction can be induced by exposure of females to X rays 9,10 especially if the flies are old 11,12 . Russell 13 reported an increase in induced monosomy in mice by examining the progeny of matings with sex-linked markers. But many aneuploids may be lethal and the dosages used by Russell were large enough to cause loss of chromosomes by breakage. Recent advances in the technique of culturing mouse oocytes in vitro (ref. 14, modified by E. P. Evans and C. E. Ford) have made it possible to circumvent these difficulties by examining meiotic chromosomes in second metaphase. The following experiment was designed to examine the effect of low doses of whole-body irradiation on chromosome segregation during first meiotic division in the oocytes of young female mice.