SCN5A Variant F1250L Detail

We estimate the penetrance of LQTS for SCN5A F1250L around 2% and the Brugada syndrome penetrance around 30%. SCN5A F1250L was found in a total of 0 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F1250L is not present in gnomAD. F1250L 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 (3 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 F1250L around 2% (0/10) and the Brugada syndrome penetrance around 30% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-5.87 1 -3.54 0.849 44 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
11997281 2002 1 0 0 1 diLQT
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 12 0 3 - -
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)
11997281 2002 HEK-tSA203 95 7.5 6.2

F1250L has 59 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
1271 15 W1271C,
1245 9 M1245I,
1218 10 S1218I, S1218T,
1281 10 c.3840+1G>A, V1281F,
1304 13 T1304M,
1217 13
1243 9 D1243N,
1274 11
1216 13 L1216V,
1285 12
1258 12
1213 13
1272 12
1210 12 F1210S,
1252 8
1283 9 L1283M,
1241 13
1309 8 R1309H, R1309C,
1242 10
1219 13 S1219N,
1251 6 V1251M,
1279 6 V1279I,
1239 15 L1239P,
1310 13
1207 14
1306 7 R1306H, R1306S,
1244 11 K1244E,
1286 12
1305 11
1273 14 c.3816delG, W1273C,
1282 7 S1282A,
1246 6
1302 14 p.L1302Vfs18,
1247 5 T1247I,
1257 10
1307 12
1256 11
1275 7 D1275N,
1255 10 L1255M,
1222 14 p.L1222LfsX7, L1222R,
1254 7
1215 9 I1215V,
1214 9 M1214T,
1212 12 p.I1212del,
1253 5 E1253G,
1284 13
1211 9
1280 10
1308 13 L1308F,
1250 0
1240 15 E1240Q,
1248 8
1276 10
1278 7 I1278N,
1266 13
1249 4 V1249D,
1208 14 E1208K, E1208X,
1277 11
1303 11 R1303Q, R1303W,