1. Copenhagen Prospective Studies on Asthma in Childhood, Herlev and Gentofte Hospital–University of Copenhagen, Gentofte, Denmark
2. Channing Division of Network Medicine, Brigham and Women’s Hospital–Harvard Medical School, Harvard University, Boston, Massachusetts
3. Department of Human Genetics, University of Chicago, Chicago, Illinois
4. Division of Pediatric Pulmonary Medicine, Golisano Children’s Hospital, University of Rochester Medical Center, Rochester, New York; and
5. Division of Physiological Chemistry II, Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden