1. Cold Spring Harbor Laboratory , Cold Spring Harbor, New York 11724, USA
2. Howard Hughes Medical Institute, Cold Spring Harbor Laboratory , Cold Spring Harbor, New York 11724, USA
3. Department of Computer Science, Johns Hopkins University , Baltimore, Maryland 21218, USA
4. Boyce Thompson Institute , Ithaca, New York 14853, USA
5. Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University , Ithaca, New York 14853, USA
6. Department of Biology, Johns Hopkins University , Baltimore, Maryland 21218, USA