SCN5A Variant E763K Detail

We estimate the penetrance of LQTS for SCN5A E763K around 1% and the Brugada syndrome penetrance around 15%. SCN5A E763K was found in a total of 3 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. E763K is present in 3 alleles in gnomAD. E763K has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Non_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (2 diagnosed with Brugada syndrome) and 5 individuals for LQTS (0 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A E763K around 1% (0/13) and the Brugada syndrome penetrance around 15% (2/13).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.96 0.684 -3.09 0.953 22 3
PROVEAN scores less than -2 are considered deleterious. REVEL scores higher than 0.5 or 0.75 are considered likely pathogenic (higher sensitivity with the former cutoff, higher specificity with the latter cutoff). A PolyPhen-2 score of 0.85 or greater is considered likely pathogenic. BLAST-PSSM reflects the evolutionary conservation of residue substitutions, more negative numbers indicate fewer observations of the specific substitution than is expected. Penetrance Density is our previously published method to calculate the average BrS/LQTS probability density in a shell of residues surrounding a residue of interest (Kroncke et al. 2019).

Reported Carrier Data

PubMed ID Year Carriers Unaffected LQT3 BrS1 Other Other Disease
LITERATURE, COHORT, AND GNOMAD: - 3 3 0 0 -
VARIANT FEATURES ALONE: - 15 13 0 2 - -
Summary totals might not agree with the literature table because of duplicate patients, which were excluded from the total counts. We do not distinguish here between multiple missense codons. Missense variants are combined across degenerate codon substitutions since codon-level data were not consistently available for curation.

E763K has 51 previously observed neighbors within 15 angstroms

A residue within a folded protein on average has nearest neighbors that fall roughly into two shells: a "nearest" neighbor around 5-6 angstroms and a second shell around 11 angstroms. All variants shown in the rightmost column have been observed in at least one individual in the literature or gnomAD.

Neighbor Distance (Angstroms) Variants Observed in Individuals
719 7
723 7 I723V,
710 9
766 6
758 8 G758E,
769 11
760 7 p.F760SfsX5,
776 11 p.Y776del,
721 12
765 7
759 6 I759V, p.I759FfsX6, c.2274delG,
792 14
764 5 M764K, M764R,
755 12
777 15 F777L,
726 10
781 15 W781X,
720 9
788 12 I788V,
711 13
724 12 T724I,
782 11 N782T,
793 15 L793F,
820 14
713 9
712 14
762 4
727 12
767 6
717 14 P717L,
770 11
756 11
814 13 R814Q,
722 9
757 11
768 10
786 12
817 12 K817E,
761 7
716 11
790 15
715 14 M715I, M715T,
725 13
784 14 F784L,
763 0 E763K, E763D,
771 12 L771V,
785 10 D785N,
730 14 N730K,
789 10 V789I, V789A,
714 9 V714D, V714A,
718 13 F718L,