Pre capture libraries

The GSD gene panel contained AGL, G6PC, GBE1, GYS2, PHKA2, PHKB, PHKG2, PYGL, SLC2A2, and SLC37A4, and NM_002863 was used for reference transcript for PYGL. Pre-capture libraries (Illumina, Inc., San Diego, CA, USA) and capture processes (Agilent Technologies, Santa Clara, CA, USA) were performed according to the manufacturer’s protocol. The captured libraries were sequenced using MiSeqDx (Illumina, Inc., San Diego, CA, USA). The raw sequence data were analysed using NextGENe software (SoftGenetics, State College, PA, USA) and annotated with ANNOVAR (http://annovar.openbioinformatics.org). Common variants were filtered using the gnomAD (http://gnomad.broadinstitute.org) and KRG (http://coda.nih.go.kr/coda/KRGDB) databases. The Human Gene Mutation Database and ClinVar were used to identify known pathogenic variants. The sequence variant was evaluated with a computational (in silico) predictive program using PolyPhen-2, SIFT, and MutationTaster. The pathogenicity of sequence variants was evaluated using the 2015 ACMG guidelines [10 ].