Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, USA. givans@cgrb.oregonstate.edu|Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, USA. givans@cgrb.oregonstate.edu|Center for Genome Research and Biocomputing, Oregon State University, Corvallis, Oregon, USA. givans@cgrb.oregonstate.edu