2.5 Variant validation
Clinically relevant small variants were validated by Sanger sequencing.
The CNVs were confirmed by gap-polymerase chain reaction (PCR) and
quantitative PCR (qPCR). The primer sequence is available on request.
The LOH was validated by Multiplex Ligation-dependent Probe
Amplification (MLPA) using SALSA MLPA Probemix ME028 Prader
Willi/Angelman (MRC Holland, Amsterdam, the Netherlands).