SCN5A Variant N1354I Detail

We estimate the penetrance of LQTS for SCN5A N1354I around 4% and the Brugada syndrome penetrance around 34%. SCN5A N1354I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. N1354I is not present in gnomAD. N1354I 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 (3 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 N1354I around 4% (0/10) and the Brugada syndrome penetrance around 34% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.919 46 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 12 0 3 - -
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.

N1354I has 61 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 6
1403 11
1357 7 A1357V,
811 9 R811H, c.2435_2436+3delTGGTAinsCGCCT, R811G,
733 13 F733L,
741 11 p.M741_T742delinsI ,
808 6 R808P, R808C, R808H,
1352 5
1406 14 G1406R, G1406E,
746 14 E746K,
1351 6 M1351V, M1351R,
739 12
1449 11 Y1449C, Y1449S,
812 9 L812Q,
1350 6 I1350T, I1350L,
731 13 T731I,
806 10 V806M,
1450 14
1353 4 V1353M,
1407 14
737 6
1358 10 G1358R, G1358W,
1433 13 G1433W, G1433R, G1433V,
1348 11 F1348L,
1404 12
750 14 Q750R,
1349 9
749 12
1431 14 S1431C,
1346 13 L1346I, L1346P,
805 9 S805L,
1359 11 K1359N, K1359M,
1356 8 c.4066_4068delTT,
1434 10 c.4299_4300insG, c.4300-1G>A, c.4299+1G>T, c.4299+2T>A, c.4299+1delG, c.4299+28C>T, c.4299delG, c.4300-2A>T, c.4299G>A, Y1434X,
1412 14 L1412F,
810 11
1408 12 G1408R,
735 10 A735V, A735T, A735E,
732 15
1360 14 F1360C,
734 9 M734V, c.2201dupT,
814 14 R814Q,
807 11
1401 14
813 14 c.2437-5C>A, c.2436+12G>A,
1354 0
1446 13
738 11
1405 11 V1405M, V1405L,
809 7
740 14 p.N740del,
815 14
736 11 L736P,
730 13 N730K,
753 13
1347 11
795 12
1428 14 A1428S, A1428V,
799 14
804 13
1402 10