Viruses physical agents affecting

Normal healthy people are generally not free from the action of mutagens, such as chemicals, physical agents, viruses, lifestyle habits including smdring and alcohol consumption. There is also scanty information on the variability of spontaneous rate of chromosomal aberrations in lymphocytes, which establishes the uppo level of normal variability in adults and children, so that a positive effect of exposure can be recognized more exactly. It is not clear at all how national rates can be different, or how urban or rural lifestyle (or environment) may affect the somatic cell aberration yield. 

---