SCN5A Variant G1329S Detail

We estimate the penetrance of LQTS for SCN5A G1329S around 44% and the Brugada syndrome penetrance around 9%. SCN5A G1329S was found in a total of 7 carriers in 2 papers and/or in gnomAD: 0 had Brugada syndrome, 3 had LQTS. G1329S is present in 2 alleles in gnomAD. G1329S has been functionally characterized in 2 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 G1329S around 44% (5/17) and the Brugada syndrome penetrance around 9% (1/17).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-5.84 1 1.66 0.878 13 55
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
21216356 2011 1 1 0 0
24667783 2015 4 2 0 0
LITERATURE, COHORT, AND GNOMAD: - 7 4 3 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)
21216356 2011
24667783 2015

G1329S has 47 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 4 V1328M,
1271 14 W1271C,
1480 15 c.4438-1C>T, c.4437+5G>A,
1765 14
1757 14
1472 7 N1472S, p.N1472del,
1315 14
1320 14 M1320I,
1333 7
1270 14 A1270S,
1477 14 K1477N,
1471 11
1762 11 I1762M, p.I1762del,
1470 13
1466 14 c.4396_4397insG,
1478 15 K1478E,
944 14
1329 0 G1329S,
1769 14
1766 11 M1766V, M1766L, M1766T,
1479 11
1473 10 F1473C, F1473S,
1334 8 I1334V,
1468 10 V1468A, V1468F,
1474 13
1324 9
1327 6
1758 13 I1758V, p.I1758del,
1330 3 A1330D, A1330T, A1330P,
1321 15 R1321K,
1323 10 V1323G,
1338 14 L1338V,
1322 11 c.3963+2T>C, c.3963+4A>G,
1337 13
1326 5 A1326S,
1763 13 V1763L, V1763M,
1332 5 P1332L, P1332Q,
1465 13 p.F1465_L1480dup,
1467 13
1476 9 Q1476R, Q1476X,
1331 5 I1331V,
1761 15 L1761F, c.5280delG, L1761H,
1475 11 p.Q1475NfsX6, Q1475L,
1469 9 I1469V,
1336 12
1325 7 N1325S,
1335 10 M1335R,