Targeted exon capture and NGS to investigate an undefined myopathy reveal RYR1 variants

Background The family under investigation consists of parents and two daughters, one being the proband. The mother and the proband have elongated facial features. The father and second daughter appear normal. The older daughter presented for elective tonsillectomy aged 8 years. She had severe masseter spasm after suxamethonium. The rest of the procedure was carried out under total intravenous anaesthesia. No blood gas analysis could be done, but...