CHROMOSOME ABERRATIONS IN IRRADIATED CELLS OF CHINESE HAMSTER GROWN IN TISSUE CULTURE

Various types of chromosome aberrations were described and their incidence recorded from analyses of metaphases derived from irradiated tissue cultures of the Chinese hamster. The aberrations included: chromatid breaks, incomplete breaks, isolocus breaks, various types of chromatid interchanges, chromatid intrachanges, minutes, and rings. The chromosomes taking part in. various configurations could usually be identified, at least into certain groups. The aberrations encountered after irradiation were of the chromatid type. The lowest dose used was 15 rads and it caused abnormalities. The graph relating the incidence of breaks to the chromosome length was not a straight line but curved suggesting a nonproportionally large increase of breaks with the long chromosomes.The advantages of the tissue culture technique and the unusual chromosome complement of the Chinese hamster were found to be, as anticipated, of great value in this study and could be utilized in various research problems.