SCN5A Variant p.L1302Vfs18 Detail

We estimate the penetrance of LQTS for SCN5A p.L1302Vfs18 around 50% and the Brugada syndrome penetrance around 9%. SCN5A p.L1302Vfs18 was found in a total of 1 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 1 had LQTS. p.L1302Vfs18 is not present in gnomAD. p.L1302Vfs18 has been functionally characterized in 1 papers. This residue is located in a Non_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 p.L1302Vfs18 around 50% (3/11) and the Brugada syndrome penetrance around 9% (1/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 6 53
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
30059973 2018 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)
30059973 2018

p.L1302Vfs18 has 48 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
1218 15 S1218I, S1218T,
1297 13
1281 5 V1281F, c.3840+1G>A,
1304 6 T1304M,
1243 10 D1243N,
1274 13
1285 8
1299 7 c.3894delC,
1673 12
1675 13
1298 11 P1298L,
1283 11 L1283M,
1309 14 R1309H, R1309C,
1226 14
1288 11 A1288G,
1242 14
1676 14 M1676T, M1676I,
1279 11 V1279I,
1239 14 L1239P,
1306 9 R1306S, R1306H,
1286 12
1305 7
1282 8 S1282A,
1246 15
1302 0 p.L1302Vfs18,
1247 12 T1247I,
1307 11
1289 13
1678 12 N1678S,
1275 14 D1275N,
1222 12 p.L1222LfsX7, L1222R,
1300 7
1674 10 F1674V,
1301 5
1284 7
1291 15
1280 10
1677 11
1308 12 L1308F,
1250 14
1670 14
1240 13 E1240Q,
1225 13 G1225K, E1225K,
1287 12
1276 14
1278 9 I1278N,
1277 10
1303 6 R1303W, R1303Q,