You know, at first we tried to use the methods we'd used for proteins and to some extent these worked. But it was, turned out to be a very different problem because the proteins have twenty components, twenty amino acids, and all different. Whereas the nucleic acids just have the four components, the mononucleotides, and you have to work out sequencing on that. And the methods used for proteins were not generally applicable. For instance they were, the amino acids were all very different chemically, so you could work out methods for separating them. Whereas the nucleic acids only had the four components, which were rather similar and so you knew, had to use quite different methods.