SCN5A Variant P1506S Detail

We estimate the penetrance of LQTS for SCN5A P1506S around 14% and the Brugada syndrome penetrance around 53%. SCN5A P1506S was found in a total of 5 carriers in 1 papers and/or in gnomAD: 4 had Brugada syndrome, 0 had LQTS. P1506S is not present in gnomAD. P1506S has been functionally characterized in 1 papers. This residue is located in a 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 (3 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 P1506S around 14% (1/15) and the Brugada syndrome penetrance around 53% (7/15).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-7.36 0.976 -1.57 0.961 55 30
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
25626866 2015 5 0 4 0
LITERATURE, COHORT, AND GNOMAD: - 5 1 0 4 -
VARIANT FEATURES ALONE: - 15 11 1 3 - -
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)
25626866 2015 HEK 49 9 -14

P1506S has 41 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 8 C1850S,
1803 11
1794 10
1849 10 H1849R,
1806 8 p.Thr1806SerfsX27,
1853 13 I1853V,
1795 6 Y1795N, Y1795C, p.Y1795_E1796insD, Y1795H,
1801 13
1511 14
1802 8
1510 13
1504 8 K1504E,
1851 10 M1851V, M1851I,
1501 13 p.L1501_K1505del, L1501V,
1507 5 p.Q1507_P1509del,
1505 5 K1505N, p.K1505_Q1507del,
1509 9 P1509T,
1808 11
1804 11
1807 6 c.5420dupA,
1798 7 W1798X,
1585 15 Y1585C,
1854 11
1797 12 I1797V,
1800 12
1793 13 M1793K,
1848 14
1817 14
1796 10
1799 8
1788 14 c.5361_5364delTGAG,
1500 15 p.K1500del,
1791 12
1852 14 D1852V,
1792 11 D1792N, D1792V, D1792Y,
1508 7
1502 12 G1502S, G1502A,
1805 6
1809 12 I1809M,
1506 0 P1506S, P1506T,
1503 10 S1503Y,