SCN5A Variant V714A Detail

We estimate the penetrance of LQTS for SCN5A V714A around 0% and the Brugada syndrome penetrance around 3%. SCN5A V714A was found in a total of 16 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V714A is present in 16 alleles in gnomAD. V714A has been functionally characterized in 1 papers. This residue is located in a Non_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 (0 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 V714A around 0% (0/26) and the Brugada syndrome penetrance around 3% (0/26).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.8 0.049 -0.89 0.851 1 1
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: - 16 16 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
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)
32533946 2020 HEK 101 6.2 4.9

V714A has 38 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 6
723 11 I723V,
710 6
766 9
715 5 M715I, M715T,
820 13
713 4
712 7
762 12
763 9 E763D, E763K,
767 6
772 13 D772N,
717 9 P717L,
770 7
781 15 W781X,
775 14
771 7 L771V,
720 7
785 13 D785N,
769 11
773 14 P773S,
722 12
760 15 p.F760SfsX5,
714 0 V714A, V714D,
776 11 p.Y776del,
768 11
721 12
765 12
716 6
817 14 K817E,
759 15 c.2274delG, I759V, p.I759FfsX6,
711 6
718 10 F718L,
724 14 T724I,
779 13 Q779X, Q779K,
764 10 M764R, M764K,
777 15 F777L,
782 11 N782T,