SCN5A Variant V1400I Detail

We estimate the penetrance of LQTS for SCN5A V1400I around 3% and the Brugada syndrome penetrance around 10%. SCN5A V1400I was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V1400I is present in 1 alleles in gnomAD. V1400I 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 (1 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 V1400I around 3% (0/11) and the Brugada syndrome penetrance around 10% (1/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-0.71 0.943 1.33 0.528 14 0
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: - 1 1 0 0 -
VARIANT FEATURES ALONE: - 15 14 0 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.

V1400I has 73 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 15
1403 9
1357 12 A1357V,
1724 13
1417 14
1430 14 D1430N,
1352 13
1426 12
1406 10 G1406E, G1406R,
1453 15
1715 11
1361 12
739 14
1745 14
1397 9 c.4190delA, c.4189delT,
1449 15 Y1449S, Y1449C,
1429 14
1723 10 T1723N,
1450 13
1725 15 P1725L,
1398 5 V1398M,
1411 6
1353 14 V1353M,
1407 7
1410 8
1716 14 p.L1716SfsX71,
1714 8 D1714G,
1358 12 G1358R, G1358W,
1396 12
1438 15 P1438L,
1404 11
1423 9 D1423H,
1362 12 R1362S, c.4083delG,
1721 10
1349 13
1431 13 S1431C,
1422 12 M1422R,
1418 15
1712 14 G1712S, G1712C,
1359 12 K1359N, K1359M,
1356 11 c.4066_4068delTT,
1412 10 L1412F,
1719 13
1408 8 G1408R,
1420 8 G1420P, G1420V, G1420D, G1420R,
1360 7 F1360C,
1401 5
1425 12
1399 6
1713 13
1427 9 A1427E, A1427S,
1424 6 I1424V,
1748 14 p.G1748del, G1748D,
738 15
1405 13 V1405L, V1405M,
1409 12 Y1409X, Y1409C,
1400 0 V1400I,
1718 9 S1718R,
1421 12
1717 10 L1717P,
1416 13 A1416G, c.4245+1G>A, A1416E, c.4245+2T>A, c.4245+1G>C,
1752 15
1722 13 N1722D,
1686 13
1749 13 I1749N,
1720 14 c.5157delC,
1415 11
1428 11 A1428V, A1428S,
1685 14
1419 13 K1419E,
1414 8 Q1414H,
1402 7
1413 11