[1] Katholieke Univ Leuven, Ctr Human Genet, I-00185 Louvain, Belgium
[2] Katholieke Univ Leuven VIB, Louvain, Belgium
[3] Hosp Sant Pau, Barcelona, Spain
[4] Univ Victor Segalen Bordeaux 2, Bordeaux, France
[5] Bambin Gesu Hosp, Lab Cytogenet, Rome, Italy
[6] Univ Roma La Sapienza, Rome, Italy