SCN5A Variant C1198S Detail

We estimate the penetrance of LQTS for SCN5A C1198S around 25% and the Brugada syndrome penetrance around 16%. SCN5A C1198S was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. C1198S is not present in gnomAD. C1198S has been functionally characterized in 0 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 (1 diagnosed with Brugada syndrome) and 5 individuals for LQTS (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A C1198S around 25% (1/10) and the Brugada syndrome penetrance around 16% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.909 13 30
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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 13 1 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.

C1198S has 31 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
1183 15 T1183I,
1184 14
1185 14 c.3553_3554delCA,
1186 13 A1186T,
1187 13 P1187Q,
1188 12
1189 11 K1189T,
1190 11 V1190F,
1191 10 W1191X,
1192 9 W1192X,
1193 8 R1193W, R1193Q,
1194 8 L1194M,
1195 7 R1195S, R1195H,
1196 5
1197 4
1198 0
1199 4 Y1199S,
1200 5 p.H1200PfsX41, H1200Y, H1200R,
1201 7 I1201M,
1202 8 V1202M,
1203 8
1204 9
1205 10
1206 11
1207 11
1208 12 E1208K, E1208X,
1209 13 T1209R,
1210 13 F1210S,
1211 14
1212 14 p.I1212del,
1213 15