SCN5A Variant I1424S Detail

We estimate the penetrance of LQTS for SCN5A I1424S around 5% and the Brugada syndrome penetrance around 21%. SCN5A I1424S was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I1424S is not present in gnomAD. I1424S has been functionally characterized in 0 papers. This residue is located in a Mild_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 (2 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 I1424S around 5% (0/10) and the Brugada syndrome penetrance around 21% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.971 22 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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 13 0 2 - -
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.

I1424S has 71 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
1355 13
1403 13
1357 13 A1357V,
896 15 C896S,
1417 12
1430 10 D1430N,
1352 12
1426 8
1406 14 G1406R, G1406E,
1453 12
1715 13
1361 13
1447 13
1444 14 L1444I,
1440 14 W1440X,
1397 13 c.4190delA, c.4189delT,
1449 11 Y1449S, Y1449C,
1429 9
1450 8
1398 8 V1398M,
1411 7
1451 14 V1451L, V1451D,
1353 15 V1353M,
1407 11
1410 11
1714 9 D1714G,
1358 14 G1358W, G1358R,
1362 12 R1362S, c.4083delG,
1438 13 P1438L,
1348 14 F1348L,
1404 14
1423 5 D1423H,
1349 14
1431 11 S1431C,
1422 7 M1422R,
1418 11
892 14 F892I,
1712 14 G1712C, G1712S,
1359 12 K1359N, K1359M,
1356 9 c.4066_4068delTT,
898 13
893 13 R893C, R893H,
1412 9 L1412F,
1408 10 G1408R,
889 13
1420 6 G1420P, G1420R, G1420D, G1420V,
1360 8 F1360C,
1401 9
1425 6
1399 11
1713 14
1454 13
1427 6 A1427E, A1427S,
1446 13
1424 0 I1424V,
1448 15 I1448L, I1448T,
1409 14 Y1409C, Y1409X,
878 11 R878L, R878C, R878H,
1400 6 V1400I,
1718 13 S1718R,
1421 7
1443 15 N1443S,
1717 14 L1717P,
1416 11 c.4245+1G>A, A1416E, A1416G, c.4245+2T>A, c.4245+1G>C,
879 12 W879R,
1415 7
1428 7 A1428S, A1428V,
1419 10 K1419E,
1414 8 Q1414H,
1402 8
1413 11