SCN5A Variant W1206C Detail

We estimate the penetrance of LQTS for SCN5A W1206C around 35% and the Brugada syndrome penetrance around 13%. SCN5A W1206C was found in a total of 0 carriers in 1 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. W1206C is not present in gnomAD. W1206C has been functionally characterized in 1 papers. This residue is located in a Non_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 W1206C around 35% (1/10) and the Brugada syndrome penetrance around 13% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-12.72 0.976 -2.85 0.817 8 29
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
18071069 2008 1 0 0 1 SCD
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.

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)
18071069 2008 Xeno 100 -2.6 0.8

W1206C has 17 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
1253 13 E1253G,
1211 9
1252 15
1256 14
1217 15
1209 6 T1209R,
1216 14 L1216V,
1316 14 R1316Q, R1316L,
1207 6
1213 10
1215 14 I1215V,
1249 14 V1249D,
1206 0
1208 8 E1208K, E1208X,
1210 5 F1210S,
1214 10 M1214T,
1212 10 p.I1212del,