The Discovery of the "Transforming Principle"
Avery’s key discovery was that the transforming substance, which produced permanent, heritable change in an organism (pneumococci), was deoxyribonucleic acid. The phenomenon of transformation, Avery wrote, "has been interpreted from a genetic point of view. The inducing substance has been likened to a gene, and the capsular antigen which is produced in response to it has been regarded as a gene product." …. ”…If the results of the present study on the chemical nature of the transforming principle are confirmed, then nucleic acids must be regarded as possessing biological specificity...."