1. Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
2. Department of Dermatology Dartmouth-Hitchcock Medical Center, Lebanon, NH 03766, USA
3. Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
4. Department of Pathology and Laboratory Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, NH 03756, USA