1. Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine, Indiana University Medical Center, Indianapolis, Indiana.
2. Department of Genetic Medicine, Weill Cornell Medical College, New York, New York.
3. Department of Medicine, University of California, Los Angeles, California.
4. Department of Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
5. Department of Medicine, Fred Hutchinson Cancer Research Center, University of Washington, Seattle, Washington.
6. Department of Epidemiology and Biostatistics, University of California, San Francisco, California.
7. National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.