SCN5A Variant Y1409C Detail

We estimate the penetrance of LQTS for SCN5A Y1409C around 6% and the Brugada syndrome penetrance around 61%. SCN5A Y1409C was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. Y1409C is not present in gnomAD. Y1409C has been functionally characterized in 1 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 (5 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 Y1409C around 6% (0/11) and the Brugada syndrome penetrance around 61% (6/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-8.77 1 -4.83 0.98 84 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
20129283 2010 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 10 0 5 - -
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)
20129283 2010

Y1409C has 65 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
1403 13
1746 14 A1746T, A1746V,
1357 15 A1357V,
1417 12
1352 12
1406 6 G1406E, G1406R,
1340 13 V1340I,
1457 12
1453 11
1757 13
1339 13 p.L1339del, L1339F,
1351 13 M1351R, M1351V,
1449 14 Y1449S, Y1449C,
1756 12 I1756V,
1461 13 T1461S,
1350 11 I1350T, I1350L,
1344 12 F1344S, F1344L,
731 15 T731I,
1450 14
1754 13
1411 7
1353 12 V1353M,
1407 7
1458 14 S1458Y,
1410 5
1714 14 D1714G,
1348 10 F1348L,
1404 10
1721 15
1349 7
1753 9 T1753A,
1346 7 L1346I, L1346P,
1418 15
1341 10
1356 14 c.4066_4068delTT,
1462 13
1412 6 L1412F,
1408 6 G1408R,
735 12 A735E, A735T, A735V,
1420 15 G1420R, G1420V, G1420D, G1420P,
1401 11
1713 14
1454 14
1338 11 L1338V,
1424 14 I1424V,
1748 14 p.G1748del, G1748D,
1405 7 V1405L, V1405M,
1409 0 Y1409X, Y1409C,
1400 12 V1400I,
1343 11
1345 6 W1345C,
1337 14
1717 14 L1717P,
1342 7
1416 10 c.4245+2T>A, A1416G, c.4245+1G>C, A1416E, c.4245+1G>A,
736 15 L736P,
1750 12 L1750F,
1752 14
1761 14 L1761F, c.5280delG, L1761H,
1749 10 I1749N,
1347 11
1415 11
1414 9 Q1414H,
1402 10
1413 5