SCN5A Variant E1253G Detail

We estimate the penetrance of LQTS for SCN5A E1253G around 1% and the Brugada syndrome penetrance around 57%. SCN5A E1253G was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. E1253G is not present in gnomAD. E1253G has been functionally characterized in 1 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 (5 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 E1253G around 1% (0/11) and the Brugada syndrome penetrance around 57% (6/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-6.85 0.999 -5.98 0.974 76 0
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 10 0 5 - -
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

E1253G has 55 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 14
1271 14 W1271C,
1245 12 M1245I,
1218 14 S1218I, S1218T,
1281 14 c.3840+1G>A, V1281F,
1217 15
1243 15 D1243N,
1274 12
1216 14 L1216V,
1258 9
1213 13
1272 10
1210 10 F1210S,
1252 5
1283 13 L1283M,
1309 9 R1309H, R1309C,
1259 12
1242 15
1251 7 V1251M,
1313 14
1279 9 V1279I,
1310 14
1207 9
1306 12 R1306S, R1306H,
1273 14 W1273C, c.3816delG,
1282 12 S1282A,
1246 10
1262 13 G1262S,
1247 10 T1247I,
1257 6
1256 6
1275 8 D1275N,
1255 8 L1255M,
1254 5
1215 10 I1215V,
1260 11 A1260D,
1206 13
1214 9 M1214T,
1212 11 p.I1212del,
1253 0 E1253G,
1211 7
1312 14
1280 13
1308 15 L1308F,
1250 5
1209 12 T1209R,
1248 11
1269 14 N1269S,
1276 11
1278 10 I1278N,
1266 10
1261 12
1249 6 V1249D,
1208 10 E1208X, E1208K,
1277 13