Department of Computer Science, Inter-Departmental Program in Bioinformatics, Department of Human Genetics and Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA Department of Computer Science, Inter-Departmental Program in Bioinformatics, Department of Human Genetics and Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA Department of Computer Science, Inter-Departmental Program in Bioinformatics, Department of Human Genetics and Department of Pathology and Laboratory Medicine, University of California, Los Angeles, CA 90095, USA.