[1] Univ Groningen, Dept Genet, Univ Med Ctr Groningen, NL-9700 RB Groningen, Netherlands
[2] Dalhousie Univ, Dept Pediat, IWK Hlth Ctr, Halifax, NS, Canada
[3] Univ Groningen, Dept Pediat Cardiol, Univ Med Ctr Groningen, NL-9700 RB Groningen, Netherlands
[4] Univ Groningen, Dept Otorhinolaryngol Head & Neck Surg, Univ Med Ctr Groningen, NL-9700 RB Groningen, Netherlands