SCN5A Variant K1504M Detail

We estimate the penetrance of LQTS for SCN5A K1504M around 50% and the Brugada syndrome penetrance around 15%. SCN5A K1504M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. K1504M is not present in gnomAD. K1504M has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a 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 (2 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A K1504M around 50% (2/10) and the Brugada syndrome penetrance around 15% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.945 11 67
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 12 2 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.

K1504M has 45 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 9 C1850S,
1855 13
1794 9
1849 12 H1849R,
1856 15
1806 15 p.Thr1806SerfsX27,
1853 13 I1853V,
1795 6 Y1795H, Y1795N, p.Y1795_E1796insD, Y1795C,
1802 15
1504 0 K1504E,
1851 9 M1851I, M1851V,
1501 7 L1501V, p.L1501_K1505del,
1857 14
1507 9 p.Q1507_P1509del,
1505 6 p.K1505_Q1507del, K1505N,
1858 12
1787 12 S1787N,
1786 12 c.5356_5357delCT, L1786R, L1786Q,
1648 14
1807 11 c.5420dupA,
1495 14 Y1495S,
1798 11 W1798X,
1496 13
1854 8
1825 14 L1825P,
1797 13 I1797V,
1793 12 M1793K,
1781 15 E1781G, E1781D,
1789 12
1499 10
1498 11 M1498R, M1498V, M1498T,
1796 11
1799 13
1788 8 c.5361_5364delTGAG,
1500 7 p.K1500del,
1791 7
1852 13 D1852V,
1792 8 D1792V, D1792Y, D1792N,
1508 13
1502 6 G1502S, G1502A,
1805 13
1497 10
1790 11 D1790G, D1790N, p.D1790del,
1506 8 P1506S, P1506T,
1503 4 S1503Y,