Using DNA, Sneed and his lab assistants can usually analyze a sample in a few days. DNA is a long, chainlike molecule that stores genetic information. It is the blueprint for cells in every living organism, Sneed said. There are four types of nucleotides, which are the links in the DNA molecule.
Genetic information is stored through the specific order of the nucleotides.
That order differs from individual to individual, he said. The more this DNA sequence differs between individuals, the more unrelated they are, Sneed explained. To positively identify a pathogen, the DNA is taken out of a cell, broken down, replicated and then analyzed using a complicated lab process called a polymerase chain reaction. From that stack, the pathogen may be identified. The sample from which the cell is taken is determined usually by the symptoms and sent in by veterinarians.