SCN5A Variant N1496K Detail

We estimate the penetrance of LQTS for SCN5A N1496K around 50% and the Brugada syndrome penetrance around 10%. SCN5A N1496K was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. N1496K is not present in gnomAD. N1496K 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 N1496K around 50% (2/10) and the Brugada syndrome penetrance around 10% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.568 7 68
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.

N1496K has 57 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 14
1785 9
1778 10
1480 12 c.4437+5G>A, c.4438-1C>T,
1773 14
1486 13 F1486L, p.F1486del,
1652 12 M1652T, M1652R,
1777 9 V1777L, V1777M,
1485 15
1487 14 M1487K, M1487L,
1492 5
1504 13 K1504E,
1477 12 K1477N,
1491 9 Q1491H,
1501 10 L1501V, p.L1501_K1505del,
1862 13
1779 13 T1779M,
1493 7 K1493X, p.K1493del, K1493R,
1858 12
1478 12 K1478E,
1776 13
1787 10 S1787N,
1786 10 c.5356_5357delCT, L1786R, L1786Q,
1648 13
1861 14 V1861F, V1861I,
1495 5 Y1495S,
1649 14 A1649V,
1774 12 N1774D, c.5321_5324dupACTT,
1496 0
1474 14
1854 14
1481 9 G1481E, G1481R, G1481V,
1781 7 E1781G, E1781D,
1789 15
1499 6
1488 13 T1488R,
1784 11 E1784K, E1784X,
1498 7 M1498R, M1498V, M1498T,
1780 11 E1780G,
1788 11 c.5361_5364delTGAG,
1500 6 p.K1500del,
1859 15
1876 14
1791 11
1482 10
1792 15 D1792V, D1792Y, D1792N,
1502 11 G1502S, G1502A,
1783 13
1484 15
1497 5
1490 11
1790 13 D1790G, D1790N, p.D1790del,
1483 11 Q1483H,
1494 8
1503 11 S1503Y,
1489 10 E1489D,
1782 12