SCN5A Variant S1503A Detail

We estimate the penetrance of LQTS for SCN5A S1503A around 26% and the Brugada syndrome penetrance around 12%. SCN5A S1503A was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. S1503A is not present in gnomAD. S1503A has been functionally characterized in 2 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (1 diagnosed with Brugada syndrome) and 5 individuals for LQTS (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A S1503A around 26% (1/10) and the Brugada syndrome penetrance around 12% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.76 0.893 0.67 0.856 10 34
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: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 13 1 1 - -
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)
22101522 2012
12796143 2003 HEK

S1503A has 37 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
1850 11 C1850S,
1855 13
1794 12
1849 13 H1849R,
1853 14 I1853V,
1795 10 Y1795C, p.Y1795_E1796insD, Y1795N, Y1795H,
1652 15 M1652R, M1652T,
1504 4 K1504E,
1851 9 M1851V, M1851I,
1501 7 L1501V, p.L1501_K1505del,
1507 13 p.Q1507_P1509del,
1505 7 p.K1505_Q1507del, K1505N,
1858 13
1787 13 S1787N,
1786 13 L1786Q, c.5356_5357delCT, L1786R,
1648 15
1807 13 c.5420dupA,
1495 12 Y1495S,
1798 14 W1798X,
1496 11
1854 10
1481 15 G1481V, G1481R, G1481E,
1781 15 E1781G, E1781D,
1789 14
1499 6
1498 10 M1498R, M1498V, M1498T,
1788 10 c.5361_5364delTGAG,
1500 6 p.K1500del,
1791 9
1852 14 D1852V,
1792 11 D1792Y, D1792N, D1792V,
1502 4 G1502S, G1502A,
1497 9
1790 14 D1790N, D1790G, p.D1790del,
1494 14
1506 10 P1506T, P1506S,
1503 0 S1503Y,