Age-related variation in sister chromatid exchanges and cell cycle kinetics in peripheral blood lymphocytes of healthy individuals

Sister chromatid exchanges (SCEs) and cell cycle kinetics were estimated in mitogen stimulated human lymphocytes from a selected group of healthy individuals. Data were examined to evaluate the relationship between SCE frequencies and cell cycle kinetics with donor's age, sex and smoking habit. No regular relationship was observed between the means SCE frequencies and donor's age, although significant differences were observed between the age groups. Correlation of dispersion coefficient (H) of SCE with donor's age were significant in male and female populations. For cell cycle kinetics, a highly significant age-dependent depression in replicative index (RI) was observed. Female donors possessed a slightly higher SCE frequency and RI, although the variations between the two sexes were not significant. Smoking habit resulted in a significant enhancement of SCEs.