This is a research book designed primarily for the young scholars which are in their early phases of research career. It can also serve as a learning resource for the university-level genetics courses and Lab techniques. It contains the established protocols covering standard preliminary genotoxicity tests of the chemicals or drugs. The battery of tests include chromosomal aberrations, micronuclei test, Mitotic Index and Histopathology. A thorough discussion has been provided to critically evaluate the results observed during the course of the study. Educators and researchers are welcome to use the materials. Please give credit when possible. If you find a mistake or would like to question please feel free to contact.