1. Service
of Genetics, Department of Pediatrics, Faculty of Medicine and Health
Sciences, Université de Sherbrooke, 3001, 12th Avenue North, Sherbrooke , Quebec, Canada J1H 5N4
2. University College London Institute of Child Health, 30
Guilford Street, London, U.K., WC1N 1EH and
3. Great Ormond Street Hospital for Children, Great Ormond
Street, London, U.K., WC1N 3JH