SCN5A Variant A1326S Detail

We estimate the penetrance of LQTS for SCN5A A1326S around 62% and the Brugada syndrome penetrance around 13%. SCN5A A1326S was found in a total of 1 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 1 had LQTS. A1326S is not present in gnomAD. A1326S has been functionally characterized in 1 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a 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 (2 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A A1326S around 62% (3/11) and the Brugada syndrome penetrance around 13% (1/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.92 0.994 0.53 0.94 15 75
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
19716085 2009 1 1 0 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 1 0 -
VARIANT FEATURES ALONE: - 15 12 2 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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
19716085 2009

A1326S has 62 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
1328 6 V1328M,
1659 13
1271 14 W1271C,
1480 12 c.4438-1C>T, c.4437+5G>A,
1773 13
1765 12
1757 14
1472 6 p.N1472del, N1472S,
1315 11
1314 13 c.3940_3941delCT,
1320 10 M1320I,
1764 13 c.5290delG, V1764F,
1333 10
1656 12
1477 10 K1477N,
1471 11
1762 10 I1762M, p.I1762del,
1470 11
1466 13 c.4396_4397insG,
1478 13 K1478E,
1767 13 Y1767C,
1660 11 I1660S, I1660V,
1329 5 G1329S,
1769 10
1766 7 M1766V, M1766T, M1766L,
1319 11 G1319V,
1768 13 I1768V,
1479 10
1473 6 F1473C, F1473S,
1334 11 I1334V,
1468 10 V1468A, V1468F,
1663 12
1657 14
1474 11
1759 14 S1759C,
1324 6
1317 15 F1317C,
1327 5
1758 13 I1758V, p.I1758del,
1318 15
1330 6 A1330D, A1330P, A1330T,
1772 15 L1772V,
1321 11 R1321K,
1323 6 V1323G,
1770 11 I1770V,
1322 7 c.3963+4A>G, c.3963+2T>C,
1312 15
1326 0 A1326S,
1763 10 V1763L, V1763M,
1311 14 L1311P,
1332 10 P1332Q, P1332L,
1465 13 p.F1465_L1480dup,
1467 13
1476 6 Q1476R, Q1476X,
1661 15 G1661R, G1661E,
1331 9 I1331V,
1761 14 L1761F, L1761H, c.5280delG,
1475 10 p.Q1475NfsX6, Q1475L,
1469 8 I1469V,
1325 5 N1325S,
1335 14 M1335R,
1664 15