Frequency of Spontaneous and Radiation-Induced Chromosomal Aberrations in Peripheral Blood Lymphocytes of Individuals of Different Ages

The frequency of spontaneous and X-ray-induced (0.25 Gy) in vitro chromosomal aberrations, as well as the level of chromosomal instability as a result of the bystander effect, in the blood lymphocytes of individuals aged from 12 to 102 years has been investigated using GTG staining of human metaphase chromosomes. The average group frequency of spontaneous chromosomal aberrations in adolescents (12-16 years), middle-aged people (33-52 years), and centenarians (90-102 years) was identical (p > 0.05), whereas it was higher in elderly people (60-70 years) due to increase of chromatid type aberrations rate (p < 0.05). In the irradiated in vitro blood lymphocytes of individuals aged 12-16 years, 33-52 years, and 90-102 years, the levels of chromosomal aberrations was not different (p > 0.05); however, the total frequency of chromosomal aberrations in individuals aged 60-70 years exceeded the value of such indices in other age groups due to the chromosomal type damages (p < 0.05). In nonirradiated blood lymphocytes of adolescents, middle-aged, and elderly individuals cocultivated with lymphocytes irradiated in vitro (0.25 Gy), the induction of the bystander effect was detected. In lymphocytes of centenarians, the development of the bystander effect was not detected.