Ion Torrent Bioinformatic analysis
Sequencing reads were aligned to hg19 reference genome. Variant calling was performed using Ion Torrent suite software v5.12 or Ion Reporter software v5.10. Called variants were filtered by allele frequencies, selecting variants with MAF <1% annotated with GnomAD database (https://gnomad.broadinstitute.org/). Nonsense, frameshift and canonical splicing variants were considered potentially pathogenic, while the other variants were classified according to Varsome database (https://varsome.com/). Called variants with the minimum coverage of 20X were analysed by Integrative Genome Viewer and confirmed by sanger sequencing. All regions covered <20X were reanalysed by sanger sequencing.