[1] UNIV PENN,CHILDRENS HOSP PHILADELPHIA,SCH MED,DIV HUMAN GENET & MOL BIOL,PHILADELPHIA,PA 19104
[2] UNIV PENN,SCH MED,DEPT PEDIAT,PHILADELPHIA,PA 19104
[3] UNIV PENN,SCH MED,DEPT GENET,PHILADELPHIA,PA 19104
[4] HOSP SICK CHILDREN,DEPT GENET,TORONTO,ON M5G 1X8,CANADA
[5] CTR RECH BIOCHIM MACROMOL,CNRS ERS 155,INSERM,U249,F-34033 MONTPELLIER,FRANCE