Source: Louisiana State University
Rare and extinct animals are preserved in jars of alcohol in natural history museum collections around the world, which provide a wealth of information on the changing biodiversity of the planet. These preserved specimens of snakes, lizards, frogs, fish and other animals can last up to 500 years when processed in a chemical called formalin. While formalin helps preserve the specimen making it rigid and durable, it poses a challenge to extracting and sequencing DNA. Furthermore, DNA degrades and splits into small fragments over time. This fragmented DNA is difficult to amplify into long informative stretches of DNA that can be used to examine evolutionary relationships among species when using older DNA sequencing technology. Therefore, scientists have not been able to effectively sequence DNA from these specimens until now.
LSU Museum of Natural Science Curator and Professor Christopher Austin and his collaborator Rutgers-Newark Assistant Professor Sara Ruane developed a protocol and tested a method for DNA sequencing thousands of genes from these intractable snake specimens. Their research was published today in the international scientific journal Molecular Ecology Resources.
"Natural history museums are repositories for extinct species. Unfortunately, naturalists in the 1800s were not collecting specimens for analyses we conduct today such as DNA sequencing. Now with these new methods, we can get the DNA from these very old specimens and sequence extinct species like the Ivory Billed Woodpecker, the Tasmanian Wolf and the Dodo Bird," Austin said.