SCN5A Variant F1418I Detail

We estimate the penetrance of LQTS for SCN5A F1418I around 15% and the Brugada syndrome penetrance around 50%. SCN5A F1418I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F1418I is not present in gnomAD. F1418I has been functionally characterized in 0 papers. This residue is located in a Hotspot region for Brugada syndrome and a Mild_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 F1418I around 15% (0/10) and the Brugada syndrome penetrance around 50% (5/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.962 75 16
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.

F1418I has 72 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
891 14 I891N, I891T,
888 15
890 14 I890T,
901 14 E901K, S901L,
896 5 C896S,
895 10 L895F,
1417 5
894 11 I894M,
1457 10
1453 10
1455 12
1715 15
1447 15
372 11
1449 14 Y1449C, Y1449S,
1452 14
1756 13 I1756V,
1461 13 T1461S,
926 14
371 12 Q371E,
1711 11 c.5131delG,
1450 11
1707 15
1411 11
1451 11 V1451D, V1451L,
1458 7 S1458Y,
1410 14
1714 12 D1714G,
897 7 G897R, G897E,
1423 12 D1423H,
927 12 N927K, N927S,
1422 9 M1422R,
1418 0
902 15
892 9 F892I,
373 11
1712 11 G1712C, G1712S,
898 7
893 8 R893H, R893C,
1462 9
1412 11 L1412F,
889 13
1709 12 p.T1709del, T1709M, T1709R,
1420 8 G1420P, G1420V, G1420R, G1420D,
900 14
1456 14
1459 9 c.4376_4379delTCTT,
1460 15 F1460L,
1425 11
1713 10
1454 7
1424 11 I1424V,
1409 15 Y1409X, Y1409C,
1400 15 V1400I,
1421 5
374 14 W374G,
1345 13 W1345C,
1416 5 A1416G, c.4245+2T>A, c.4245+1G>C, c.4245+1G>A, A1416E,
1760 11
370 13 T370M,
879 14 W879R,
1761 13 c.5280delG, L1761H, L1761F,
923 13
375 14
899 13
1710 9 S1710L,
1415 6
1419 6 K1419E,
1414 8 Q1414H,
931 12
1463 12 N1463Y,
1413 10