In Situ Hybridization: Marriage Between Molecular Biology and Cytology

Abstract

After the discovery that RNA molecules with sequences complementary to those of DNA can anneal with the template to form DNA-RNA hybrid molecules, biologists began to consider the possibility of DNA-RNA hybridization in cytological preparations. If a particular species of RNA is made radioactive and if such RNA molecules form hybrids with complementary DNA in the cell nuclei and chromosomes, the cytological locations of this DNA (or genes) can be identified in the auto radiographs. In principle, this procedure should be quite feasible; but in practice a number of technical problems must be solved. A number of cytologists, including myself, made such attempts but failed.