RESUMEN
OBJECTIVE: To establish and compare the frequency and spectrum of chromosome aberrations under X radiation exposure in vitro in dose 0.25 Gy peripheral blood lymphocytes of the elderly and centenarians. MATERIAL AND METHODS: Material of cytogenetic research were peripheral blood lymphocytes from 11 elderly and 10 centenarians, which were irradiated in vitro in dose 0.25 Gy and cultured by generally accepted semi micromethod; slides of metaphase chromosomes were GTG stained and analyzed under the microscope with magnification x 1000. RESULTS: Under irradiation of blood in vitro the mean group frequencies of chromosome aberrations exceeded such without irradiation (Ñ < 0.001) and were 11.60 ± 0.95 аnd 6.82 ± 0.63 per 100 cells in the elderly and the centenar ians, accordingly. Radiation induced increase in the frequency of chromosomal injuries occurred due to chromo some type aberrations which are markers of radiation exposure. In the elderly the elevated frequency of chromatid type aberrations also was registered what is considered a sign of chromosome instability. CONCLUSIONS: The results indicate increased sensitivity the blood lymphocytes from the elderly to radiation expo sure in low doses and allow to assume the advantage of persons with hereditary determined chromosomal stability in achieving longevity.