Soy Scientists to Fill "Library" with Genetic BookmarksBy Jan Suszkiw
March 21, 2008
Soybean varieties with improved yield, pest resistance, protein and oil quality and quantity and other traits are among the benefits expected of a new project in which Agricultural Research Service (ARS) scientists will create a "library" of 50,000 DNA markers called single nucleotide polymorphisms (SNPs).
Geneticists David Hyten and Perry Cregan will "stock" the library as part of their ongoing studies with SNP DNA markers at ARS' Soybean Genomics and Improvement Research Unit in Beltsville, Md. The United Soybean Board (USB) is funding the $2.9 million, three-year project from the organization's soybean checkoff program.
The library's completion will provide soybean researchers and breeders with a valuable resource to use in characterizing the genetic variation available for soybean improvement. For example, they'll be able to determine the position and characteristics of alleles, or alternate forms of genes, within the oilseed crop's 20 chromosomes.
A goal is to genotype nearly 20,000 lines, called accessions, in the USDA soybean germplasm collection, which ARS curator and collaborator Randall Nelson maintains on the University of Illinois campus at Urbana-Champaign. The library's anticipated 50,000 SNPs will help researchers to take the next step in applying the soybean whole genome-sequence datareleased by the U.S. Department of Energy's Joint Genome Instituteto make soybean breeding more efficient and precise. Of particular interest is using SNP marker technology to rapidly identify plants that carry important traits like high-quality oil and resistance to pests including soybean cyst nematodes.
The SNPs themselves are small changes, or variations, in the sequence of four biochemical "letters"A (adenine), C (cytosine), T (thymine) and G (guanine)that make up an organism's DNA "alphabet." Cregan and Hyten, together with their ARS and university colleagues, have so far identified 43,000 SNPs in soybean and mapped the genome locations of 15,000 of them.
ARS is the U.S. Department of Agriculture's chief scientific research agency. The USB is made up of 68 farmer-directors who oversee investments of the soybean checkoff on behalf of all U.S. soybean farmers.