 In 1939, Stanley and Max Lauffer (1914) separated the virus into protein and nucleic acid, which was shown by Stanley's postdoctoral fellow Hubert S. Loring to be specifically RNA.The discovery of RNA in the particles was important because in 1928, Fred Griffith (c.1879–1941) provided the first evidence that its "cousin", DNA, formed genes.In Pasteur's day, and for many years after his death, the word "virus" was used to describe any cause of infectious disease.