DNA Deoxyribonucleic acid and ribonucleic acid are two chemical substances involved in transmitting genetic information from parent to offspring. It was known early into the 20th century that chromosomes, the genetic material of cells, contained DNA. In 1944, Oswald T. Avery, Colin M. MacLeod, and Maclyn McCarty concluded that DNA was the basic genetic component of chromosomes. Later, RNA would be proven to regulate protein synthesis. (Miller, 139) DNA is the genetic material found in most viruses and in all cellular organisms. Some viruses do not have DNA, but contain RNA instead. Depending on the organism, most DNA is found within a single chromosome lik