SCN5A Variant N782T Detail

We estimate the penetrance of LQTS for SCN5A N782T around 2% and the Brugada syndrome penetrance around 51%. SCN5A N782T was found in a total of 1 carriers in 2 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. N782T is not present in gnomAD. N782T has been functionally characterized in 2 papers. This residue is located in a 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 (4 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 N782T around 2% (0/11) and the Brugada syndrome penetrance around 51% (5/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-5.94 0.034 -2.76 0.954 69 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
20123697 2010 1 0 1 0
26729854 2016 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 11 0 4 - -
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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
20123697 2010
26729854 2016

N782T has 48 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 14
723 13 I723V,
710 15
766 13
821 14
769 13
773 10 P773S,
760 13 p.F760SfsX5,
780 5
776 4 p.Y776del,
765 12
764 7 M764R, M764K,
777 6 F777L,
791 15 L791F,
819 14
826 15 N826D,
818 15
781 6 W781X,
720 12
788 10 I788V,
711 14
782 0 N782T,
820 10
762 13
774 13 p.Y774TfsX28, Y774D, c.2320delT, Y774C,
767 7
770 12
775 11
814 14 R814Q,
816 14 F816L, F816Y,
813 14 c.2437-5C>A, c.2436+12G>A,
768 8
786 7
817 10 K817E,
761 13
779 5 Q779X, Q779K,
778 8
790 13
715 15 M715I, M715T,
784 7 F784L,
763 11 E763K, E763D,
772 11 D772N,
771 9 L771V,
785 6 D785N,
783 5 I783T,
789 11 V789I, V789A,
714 11 V714D, V714A,
787 10