A rapid procedure to detect insitu DNA/RNA hybrids

Abstract We developed a new method for detecting DNA/RNA hybrids formed in situ using anti- DNA RNA antibodies and the Peroxidase-antiperoxidase immunohistochemical procedure. Using RNA synthesised in vitro from cloned Drosophila histone genes (pDm 500H), we localized by this procedure, the histone genes to the 39 D-E region of the left arm of the second chromosome. This method has several advantages compared to conventional procedures.