Fig. 2: NGS data visualization and identification of KCNQ1 variants.

Graphics output of the IGV alignments of NGS reads from the index patient at two KCNQ1 genomic positions leading to the identification of the pathogenic variant c.776 G > T in exon 5 (variant #1 in a) and a previously undescribed variant c.1686−9 T > C in intron 13 of the KCNQ1 gene (variant #8 in b). A unique tag (#) ID number was assigned to each identified variant. The figure was assembled using scalable vector graphic files exported from the IGV application. NGS reads (horizontal grey bars) alignments to the reference genome sequence (RefSeq NC_000011.9) are displayed at two scales, 2800 bp and a zoomed version at 80 bp. Both nucleotide variants #1 and #8 were detected in the heterozygous state and the percentage of reads corresponding to each alternative nucleotide are shown with round brackets. Coverage graphs are shown with grey vertical bars and the coverage range is indicated in square brackets. Exon (E)–intron (i) structure of each displayed KCNQ1 regions are represented with blue boxes and lines, respectively. The complete descriptions of the ten KCNQ1 variants identified in the index patient’s genomic DNA by targeted NGS are shown in Table 1 with the same tag (#) ID numbers used in this figure.