1. Genetics, Genomics, and Bioinformatics Graduate Program, University of California, Riverside, California 92521
2. Department of Genetics, University of North Carolina at Chapel Hill, North Carolina 27599
3. The Jackson Laboratory for Genomic Medicine, Farmington, Connecticut 06032
4. Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, California 92521
5. Department of Botany and Plant Sciences, University of California, Riverside, California 92521
6. Friedrich Miescher Laboratory of the Max Planck Society, 72076 Tübingen, Germany