SCN5A Variant G1420C Detail

We estimate the penetrance of LQTS for SCN5A G1420C around 5% and the Brugada syndrome penetrance around 60%. SCN5A G1420C was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. G1420C is not present in gnomAD. G1420C has been functionally characterized in 0 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 G1420C around 5% (0/10) and the Brugada syndrome penetrance around 60% (5/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.945 92 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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
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.

G1420C 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
901 12 S901L, E901K,
896 12 C896S,
1417 9
1430 15 D1430N,
1426 11
1453 14
1715 9
1687 13
372 13
1756 15 I1756V,
1429 14
1711 11 c.5131delG,
1450 12
1707 14
1398 12 V1398M,
1411 9
1407 14
1458 14 S1458Y,
1410 12
1706 14 Q1706H,
1716 12 p.L1716SfsX71,
1714 6 D1714G,
376 13 R376C, R376H,
897 13 G897R, G897E,
1423 5 D1423H,
1721 15
1422 6 M1422R,
1418 8
892 14 F892I,
373 11
1712 8 G1712S, G1712C,
898 9
893 10 R893C, R893H,
1412 11 L1412F,
1719 14
1408 13 G1408R,
889 14
1709 15 p.T1709del, T1709M, T1709R,
1420 0 G1420P, G1420D, G1420R, G1420V,
1360 13 F1360C,
1401 13
1425 9
1399 12
1713 10
1454 13
1427 11 A1427S, A1427E,
1424 6 I1424V,
1409 15 Y1409C, Y1409X,
878 11 R878L, R878H, R878C,
1400 8 V1400I,
1421 5
1718 11 S1718R,
1717 11 L1717P,
1416 10 A1416E, c.4245+1G>A, c.4245+2T>A, A1416G, c.4245+1G>C,
1752 14
879 12 W879R,
1686 12
375 12
1710 11 S1710L,
1415 7
1428 12 A1428S, A1428V,
1419 5 K1419E,
1414 6 Q1414H,
1402 13
1413 11