Scientists Probe Genetic Makeup of Chickens

On the campus of Michigan State University, there's a chicken called "Female #256." She's the Red Jungle Fowl chicken (Gallus gallus) whose blood samples gave researchers the one billion base pairs of DNA needed to create the first complete gene sequence of any barnyard animal.

Jerry Dodgson, a molecular biologist at the East Lansing campus, created a physical map with her DNA. His colleagues, Agricultural Research Service (ARS) geneticist Hans H. Cheng and others from the nearby ARS Avian Disease and Oncology Laboratory, created a genetic map using DNA from progeny of "Male #10394" from the same Red Jungle Fowl line, and a White Leghorn female from an experimental inbred line of chickens.

The genetic map is like an interstate map--a broad overview of the order of the genes-- while the physical map is more detailed, like a street map.

An international team, led by Richard Wilson from the Washington University School of Medicine in St. Louis, Mo., used these two maps as the basis for their sequencing of chicken genes. A paper on the team's expanded version of Dodgson's physical map appeared earlier this month in Naturemagazine.

The National Institutes of Health's National Human Genome Research Institute funded the project. The sequence is available online at:

http://www.ncbi.nih.gov/Genbank

Chickens are important to studies of viruses and cancers, as well as being important agriculturally. Wild Red Jungle Fowl are the ancestors of today's birds. The breed has survived at large for about 8,000 years--rare for a wild ancestor of a domesticated animal.

The ARS collection at East Lansing that houses "Female #256" includes over 50 inbred lines of chickens ideally suited for genetic studies. It is one of the world's best collections, maintained since the 1930s. "Female #256" came to East Lansing from a line maintained by the University of California at Davis.

ARS is the U.S. Department of Agriculture's chief scientific research agency.