SCN5A Variant K1499M Detail

We estimate the penetrance of LQTS for SCN5A K1499M around 50% and the Brugada syndrome penetrance around 11%. SCN5A K1499M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. K1499M is not present in gnomAD. K1499M has been functionally characterized in 0 papers. This residue is located in a Non_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 K1499M around 50% (2/10) and the Brugada syndrome penetrance around 11% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.95 5 66
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.

K1499M has 32 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
1855 12
1785 14
1480 13 c.4437+5G>A, c.4438-1C>T,
1652 15 M1652R, M1652T,
1777 14 V1777M, V1777L,
1492 10
1504 10 K1504E,
1491 12 Q1491H,
1851 12 M1851V, M1851I,
1501 7 L1501V, p.L1501_K1505del,
1493 12 K1493R, K1493X, p.K1493del,
1505 13 p.K1505_Q1507del, K1505N,
1858 13
1787 14 S1787N,
1786 13 L1786Q, c.5356_5357delCT, L1786R,
1495 5 Y1495S,
1496 6
1854 12
1481 10 G1481V, G1481R, G1481E,
1781 12 E1781G, E1781D,
1499 0
1498 6 M1498R, M1498V, M1498T,
1788 12 c.5361_5364delTGAG,
1500 6 p.K1500del,
1876 12
1791 11
1482 11
1502 6 G1502S, G1502A,
1497 6
1483 13 Q1483H,
1494 10
1503 6 S1503Y,