SCN5A Variant W1271C Detail

We estimate the penetrance of LQTS for SCN5A W1271C around 15% and the Brugada syndrome penetrance around 50%. SCN5A W1271C was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. W1271C is not present in gnomAD. W1271C has been functionally characterized in 1 papers. This residue is located in a Mild_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 (4 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 W1271C around 15% (0/11) and the Brugada syndrome penetrance around 50% (5/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-12.66 1 -6.29 0.941 61 12
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
20129283 2010 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 11 0 4 - -
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)
20129283 2010

W1271C has 50 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
1267 13
1328 10 V1328M,
1271 0 W1271C,
1315 8
1274 6
1314 11 c.3940_3941delCT,
1320 13 M1320I,
1666 14
1272 6
1270 5 A1270S,
1309 9 R1309H, R1309C,
1265 13
1313 9
1279 15 V1279I,
1329 14 G1329S,
1310 10
1316 10 R1316L, R1316Q,
1306 15 R1306S, R1306H,
1305 13
1273 9 W1273C, c.3816delG,
1663 14
1324 10
1317 14 F1317C,
1327 12
1257 13
1268 11 T1268S, T1268N,
1307 12
1275 8 D1275N,
1321 12 R1321K,
1323 14 V1323G,
1254 14
1215 13 I1215V,
1212 13 p.I1212del,
1253 14 E1253G,
1211 14
1312 5
1326 14 A1326S,
1311 7 L1311P,
1308 9 L1308F,
1250 15
1670 14
1331 14 I1331V,
1269 6 N1269S,
1325 11 N1325S,
1276 12
1278 12 I1278N,
1266 10
1261 12
1208 14 E1208K, E1208X,
1277 11