1. Institute for Interdisciplinary Information Sciences, Tsinghua University , Beijing 100084, China
2. Department of Computer Science, Purdue University , IN 47907, United States
3. Genomic Analysis Laboratory, The Salk Institute for Biological Studies , La Jolla, CA 92037, United States
4. Bioinformatics Program, University of California , San Diego, La Jolla, CA 92093, United States
5. Institute for Artificial Intelligence, Peking University , Beijing 100091, China