1 Department of Biomedical Informatics, Columbia University, New York, NY USA. Electronic address: chunhua@columbia.edu.
2 Department of Biomedical Informatics, Columbia University, New York, NY USA; Department of Medicine, New York University Medical Center, New York, NY USA.
3 Department of Biomedical Informatics, Columbia University, New York, NY USA; Department of Computer Science, Nanjing University of Science and Technology, Nanjing, China.
4 Department of Pediatrics, Memorial Sloan Kettering Cancer Center, New York, NY USA.