[1] Univ Lausanne, Div Expt Pathol, CH-1011 Lausanne, Switzerland
[2] Univ Lausanne, Inst Pathol, Div Clin Pathol, CH-1011 Lausanne, Switzerland
[3] Univ Lausanne, Dept Pediat Surg, CH-1011 Lausanne, Switzerland
[4] Univ Geneva, Dept Orthoped, Geneva, Switzerland
[5] Univ Geneva, Dept Neurosurg, Geneva, Switzerland
[6] Univ Turin, Dept Genet Biol & Biochem, Turin, Italy