SCN5A Variant W1345C Detail

We estimate the penetrance of LQTS for SCN5A W1345C around 8% and the Brugada syndrome penetrance around 70%. SCN5A W1345C was found in a total of 3 carriers in 3 papers and/or in gnomAD: 3 had Brugada syndrome, 0 had LQTS. W1345C is not present in gnomAD. W1345C has been functionally characterized in 4 papers. This residue is located in a Hotspot region for Brugada syndrome and a Non_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (6 diagnosed with Brugada syndrome) and 5 individuals for LQTS (0 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A W1345C around 8% (0/13) and the Brugada syndrome penetrance around 70% (9/13).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-12.67 1 -5.48 0.939 90 2
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
20339501 2010 2 0 2 0
29574140 2018 1 0 1 0
30059973 2018 2 2 0 0
LITERATURE, COHORT, AND GNOMAD: - 3 0 0 3 -
VARIANT FEATURES ALONE: - 15 9 0 6 - -
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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
30059973 2018
29574140 2018
32533946 2020 HEK 12
20339501 2010

W1345C has 66 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
1417 11
1352 13
1406 11 G1406R, G1406E,
1340 8 V1340I,
1457 7
1453 7
1455 12
1757 13
1339 10 L1339F, p.L1339del,
1351 12 M1351R, M1351V,
1449 12 Y1449S, Y1449C,
1452 13
1756 13 I1756V,
1461 8 T1461S,
812 14 L812Q,
1350 11 I1350L, I1350T,
1344 6 F1344L, F1344S,
731 15 T731I,
1450 12
1411 10
1451 15 V1451L, V1451D,
1353 14 V1353M,
825 14
1407 12
1458 9 S1458Y,
1410 10
1348 7 F1348L,
1404 14
1464 12 c.4389_4396delCCTCTTTA, L1464P,
1349 8
1753 12 T1753A,
1346 7 L1346P, L1346I,
1418 13
1341 5
1334 14 I1334V,
1462 9
1412 7 L1412F,
1408 10 G1408R,
735 14 A735E, A735T, A735V,
1456 10
1459 13 c.4376_4379delTCTT,
1460 11 F1460L,
816 14 F816L, F816Y,
1454 11
1338 9 L1338V,
1405 11 V1405M, V1405L,
1409 6 Y1409C, Y1409X,
815 13
1421 15
1343 7
1345 0 W1345C,
1337 10
1342 5
1416 8 c.4245+1G>A, A1416E, A1416G, c.4245+2T>A, c.4245+1G>C,
1465 12 p.F1465_L1480dup,
1760 14
1761 12 L1761F, L1761H, c.5280delG,
1347 8
1336 14
1415 10
1335 15 M1335R,
828 14 L828V,
1414 11 Q1414H,
1402 13
1463 13 N1463Y,
1413 7