SCN5A Variant K1478Q Detail

We estimate the penetrance of LQTS for SCN5A K1478Q around 31% and the Brugada syndrome penetrance around 11%. SCN5A K1478Q was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. K1478Q is not present in gnomAD. K1478Q has been functionally characterized in 0 papers. This residue is located in a Non_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 (1 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 K1478Q around 31% (1/10) 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 0.719 7 40
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 13 1 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.

K1478Q 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
1480 8 c.4438-1C>T, c.4437+5G>A,
1773 10
943 14 S943N,
1486 11 p.F1486del, F1486L,
1472 11 p.N1472del, N1472S,
1777 11 V1777L, V1777M,
1485 10
1487 8 M1487L, M1487K,
1492 8
1477 6 K1477N,
1491 13 Q1491H,
1471 11
1493 13 K1493X, K1493R, p.K1493del,
1470 13
1478 0 K1478E,
1776 13
1329 15 G1329S,
1769 14
1495 11 Y1495S,
1774 13 c.5321_5324dupACTT, N1774D,
1479 6
1473 10 F1473C, F1473S,
1496 12
1474 5
1481 7 G1481V, G1481R, G1481E,
1781 15 E1781G, E1781D,
1772 15 L1772V,
1488 11 T1488R,
1780 14 E1780G,
1770 14 I1770V,
1482 5
1322 12 c.3963+4A>G, c.3963+2T>C,
1326 13 A1326S,
1476 7 Q1476X, Q1476R,
1484 6
1490 14
1475 5 p.Q1475NfsX6, Q1475L,
1469 15 I1469V,
1483 7 Q1483H,
1325 13 N1325S,
1489 9 E1489D,