URBANA The trade in ivory was largely outlawed in 1989, but poaching continues and remains a serious threat to the African elephant. Seizures of large amounts of ivory, sometimes over a ton, continue to occur. Research by Alfred Roca, an assistant professor at the university, could be the basis for the development of new law enforcement tools.
Roca has found a way to determine where the ivory comes from. With funding from the Division of International Conservation of the U.S. Fish and Wildlife Service, he and his collaborators have sampled elephants at 22 locations in 13 African countries to get sequences of their mitochondrial DNA (mtDNA).
mtDNA is the DNA located in mitochondria, structures within cells that convert the chemical energy from food into a form the cells can use. Most DNA is "nuclear," found in the cell nucleus. What makes mtDNA a good marker for tracing the origin of ivory is first, that it is transmitted only by females and second, the fact that female elephants do not migrate between herds.
Other researchers have found that it is possible to get fragments of mtDNA from ivory and that is possible to amplify those fragments. Roca and his collaborators wanted to match these fragments to elephants from a specific location.
To do this, Nicholas Georgiadis, a researcher who was in Kenya and is now at Washington State, used a rifle to shoot a biopsy dart, which would hit the side of the elephant and scrape a small piece (less than a centimeter square) of skin from the elephant and fall off.
"It's like a biting insect," said Roca. "The hardest part was finding the dart after it fell off. Georgiadis never had a problem with an elephant unless it was already predisposed to be hostile to humans."
Georgiadis collected 653 samples that Yasuko Ishida, a researcher in Roca's lab, then sequenced and analyzed. She found eight distinct subclades, or subdivisions, of mtDNA previous research had detected on
|Contact: Susan Jongeneel|
University of Illinois College of Agricultural, Consumer and Environmental Sciences