SCN5A Variant C182R Detail

We estimate the penetrance of LQTS for SCN5A C182R around 10% and the Brugada syndrome penetrance around 43%. SCN5A C182R was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. C182R is not present in gnomAD. C182R 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 C182R around 10% (0/11) and the Brugada syndrome penetrance around 43% (4/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-11.49 0.998 -2.07 0.959 47 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 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)
20129283 2010

C182R has 26 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
175 14 K175N,
113 6 V113A, V113I,
194 15
188 10
178 13 A178G,
190 13 R190W, R190L, R190Q, R190G,
179 12 R179X, R179Q,
177 12 L177P,
189 11
121 14 R121Q, R121W,
198 14
181 5
176 9
172 14
185 6 A185V, A185T,
115 13 S115G,
186 8
182 0 C182R, C182Y,
173 14
112 10 Y112C,
114 9
184 7 H184R,
116 15
187 9 T187I, T187S,
180 6 G180V,
183 4