SCN5A Variant K1492Q Detail

We estimate the penetrance of LQTS for SCN5A K1492Q around 42% and the Brugada syndrome penetrance around 17%. SCN5A K1492Q was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. K1492Q is not present in gnomAD. K1492Q 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 K1492Q around 42% (2/10) and the Brugada syndrome penetrance around 17% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.941 15 55
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.

K1492Q has 46 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
1785 11
1778 12
1480 12 c.4437+5G>A, c.4438-1C>T,
1773 13
1486 8 F1486L, p.F1486del,
1652 14 M1652R, M1652T,
1777 9 V1777M, V1777L,
1485 11
1487 10 M1487K, M1487L,
1492 0
1477 11 K1477N,
1491 6 Q1491H,
1501 14 L1501V, p.L1501_K1505del,
1862 14
1779 13 T1779M,
1493 6 K1493R, K1493X, p.K1493del,
1478 8 K1478E,
1776 12
1787 14 S1787N,
1786 13 L1786Q, c.5356_5357delCT, L1786R,
1495 5 Y1495S,
1774 13 c.5321_5324dupACTT, N1774D,
1479 13
1496 5
1474 11
1481 8 G1481V, G1481R, G1481E,
1781 9 E1781G, E1781D,
1499 10
1488 8 T1488R,
1784 11 E1784X, E1784K,
1498 10 M1498R, M1498V, M1498T,
1780 10 E1780G,
1500 11 p.K1500del,
1876 14
1482 7
1502 15 G1502S, G1502A,
1783 13
1476 14 Q1476R, Q1476X,
1484 10
1497 9
1490 8
1475 13 Q1475L, p.Q1475NfsX6,
1483 7 Q1483H,
1494 8
1489 6 E1489D,
1782 14