Roger E. Stevenson, MD, is Senior Clinical Geneticist at Greenwood Genetic Center in Greenwood, South Carolina.

Judith G. Hall, MD, is Professor Emerita of Pediatrics and Medical Genetics at the University of British Columbia based at Children's & Women's Health Centre of British Columbia in Vancouver.

David B. Everman, MD, is an Associate Clinical Geneticist at Greenwood Genetic Center in Greenville, South Carolina.

Benjamin D. Solomon, MD, is Chief of the Division of Medical Genomics at the Inova Translational Medicine Institute and Associate Professor of Pediatrics at the Virginia Commonwealth University School of Medicine.