SCN5A Variant F1293S Detail

We estimate the penetrance of LQTS for SCN5A F1293S around 0% and the Brugada syndrome penetrance around 3%. SCN5A F1293S was found in a total of 171 carriers in 6 papers and/or in gnomAD: 4 had Brugada syndrome, 0 had LQTS. F1293S is present in 165 alleles in gnomAD. F1293S has been functionally characterized in 8 papers. This residue is located in a Non_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 (1 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 F1293S around 0% (0/181) and the Brugada syndrome penetrance around 3% (5/181).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-4.74 0.46 0.42 0.625 5 5
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
29167113 2018 1 0 0 1 IBS
11901046 2002 1 0 1 0
22885917 2012 1 0 1 0
23321620 2013 1 0 1 0
25998140 2015 1 0 1 0
20129283 2010 2 0 0 0
LITERATURE, COHORT, AND GNOMAD: - 171 167 0 4 -
VARIANT FEATURES ALONE: - 15 14 0 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)
29167113 2018 HEK 43 6.3 1.1
11901046 2002
15851227 2004
15898185 2004
22885917 2012
23321620 2013
25998140 2015
20129283 2010

F1293S has 15 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
1292 6
1734 12
1291 9
1298 9 P1298L,
1288 12 A1288G,
1289 12
1297 8
1735 12
1296 6 M1296T,
1299 12 c.3894delC,
1290 12
1736 12
1293 0 F1293S,
1294 5 A1294G,
1295 8 E1295K,