Cytological factors and their predictive role in comparative radiosensitivity: a general summary.

Various cytological factors, including interphase chromosome volume (ICV), nuclear volume (NV), cell volume, DNA content per nucleus and per chromosome, have been reviewed to determine their usefulness as indices to predict radiosensitivity. Fourteen topics are discussed. They are: a historical development of the concept of using karyotypic features to estimate radiosensitivity; interrelationships between cellular parameters; relationship of the karyotype to the duration of mitosis and meiosis; relationships between chronic and acute irradiation and ICV using several radiobiological end points for woody and herbaceous species; correlations between dose and cellular parameters ftween chromosome aberrations and cellular characteristics after chronic irradiation; polyploidy and plant radiosensitivity; radiation-induced petal mutations in plants and their relationship to cellular parameters; correlations between mean survival time facter irradiation and cellular parameters in amphibians and higher plants; correlations between radiobiological end points and cellular parameters after whole-body irradiation in amphibians. insects and mammals; correlations between radiosensitivity and cellular parameters in diverse single-cell organisms; correlations between radiobiological end points and cellular parameters in higher plants irradiated with neutrons and the value of cell parameters to estimate relative biological effectiveness (RBE); and energy absorption and trends in radiosensitivity among species and radiobiological end points. It is concluded that ICV is usually the most useful parameter for predicting radiosensitivity.