1. Department of Pediatrics, Pennsylvania State University College of Medicine, Hershey, Pennsylvania;
2. Department of Pathology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania;
3. Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts;
4. Department of Medicine, Temple University School of Medicine, Philadelphia, Pennsylvania; and
5. Department of Biochemistry and Molecular Biology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania