ORNL: Populus SNP Dataset Holds Promise for Biofuels

(Oak Ridge National Laboratory/Biomass Magazine) Researchers at the Department of Energy’s Oak Ridge National Laboratory have released the largest-ever single nucleotide polymorphism (SNP) dataset of genetic variations in poplar trees, information useful to plant scientists as well as researchers in the fields of biofuels, materials science, and secondary plant metabolism.

For nearly 10 years, researchers with DOE’s BioEnergy Science Center, a DOE Bioenergy Research Center led by ORNL, have studied the genome of Populus—a fast-growing perennial tree recognized for its economic potential in biofuels production. Recently, they released the Genome-Wide Association Study (GWAS) dataset that comprises more than 28 million single nucleotide polymorphisms, or SNPs, derived from approximately 900 resequenced poplar genotypes. Each SNP represents a variation in a single DNA nucleotide, or building block, and can act as a biological marker, helping scientists locate genes associated with certain characteristics, conditions, or diseases.

The data “gives us unprecedented statistical power to link DNA changes to phenotypes [physical traits],” said Gerald Tuskan, a corporate fellow and leader of the Plant Systems Biology group in ORNL’s Biosciences Division. Tuskan will present the GWAS data today at the Plant & Animal Genome Conference in San Diego. The results of this analysis have been used to seek genetic control of cell-wall recalcitrance—a natural characteristic of plant cell walls that prevents the release of sugars under microbial conversion and inhibits biofuels production.

BESC scientists are also using the dataset to identify the molecular mechanisms controlling deposition of lignin in plant structures. Lignin, the polymer that strengthens plant cell walls, acts as a barrier to accessing cellulose and thereby preventing cellulose breakdown into simple sugars for fermentation. READ MORE and MORE (Oak Ridge National Laboratory)