SCN5A Variant Y1449S Detail

We estimate the penetrance of LQTS for SCN5A Y1449S around 4% and the Brugada syndrome penetrance around 53%. SCN5A Y1449S was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. Y1449S is not present in gnomAD. Y1449S 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 (4 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 Y1449S around 4% (0/11) and the Brugada syndrome penetrance around 53% (5/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-8.59 0.977 -5.9 0.967 68 1
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
24775617 2013 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 11 0 4 - -
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)
24775617 2013

Y1449S 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
888 14
1355 8
1357 12 A1357V,
1430 14 D1430N,
808 15 R808H, R808C, R808P,
1352 7
1445 11 Y1445H,
1457 12
1453 7
1455 11
1447 9
1444 12 L1444I,
1351 6 M1351V, M1351R,
1449 0 Y1449C, Y1449S,
1452 6
812 12 L812Q,
1350 11 I1350L, I1350T,
1429 11
1344 13 F1344L, F1344S,
806 13 V806M,
1450 4
1411 11
1451 7 V1451D, V1451L,
1353 11 V1353M,
1407 15
1458 13 S1458Y,
1348 6 F1348L,
1349 9
1431 13 S1431C,
1422 14 M1422R,
1346 13 L1346I, L1346P,
1418 14
805 14 S805L,
892 13 F892I,
1359 12 K1359M, K1359N,
1356 8 c.4066_4068delTT,
1412 9 L1412F,
810 14
1408 11 G1408R,
889 13
1456 11
1360 13 F1360C,
1459 14 c.4376_4379delTCTT,
1401 14
1425 9
1454 9
1354 11
1427 13 A1427S, A1427E,
1446 7
1424 11 I1424V,
1448 6 I1448L, I1448T,
1405 14 V1405L, V1405M,
809 11
1409 14 Y1409X, Y1409C,
1400 15 V1400I,
1421 12
885 15
1345 12 W1345C,
1443 12 N1443S,
1416 12 A1416G, c.4245+1G>C, c.4245+1G>A, A1416E, c.4245+2T>A,
1347 11
1415 10
1428 9 A1428S, A1428V,
1414 14 Q1414H,
1402 9
1413 14