SCN5A Variant F198C Detail

We estimate the penetrance of LQTS for SCN5A F198C around 5% and the Brugada syndrome penetrance around 16%. SCN5A F198C was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F198C is not present in gnomAD. F198C has been functionally characterized in 0 papers. This residue is located in a Mild_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 F198C around 5% (0/10) 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 0.978 14 1
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 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.

F198C has 54 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
198 0
193 11 W193R, W193X,
195 7
170 12 F170I,
184 12 H184R,
228 12 K228R,
183 15
227 14 L227P,
171 8
137 13 I137V,
197 5
221 15
196 7
190 13 R190L, R190Q, R190G, R190W,
169 9
177 13 L177P,
189 7
222 14 R222X, R222L, R222Q,
224 13 L224F,
174 11 V174I,
133 15
182 14 C182Y, C182R,
191 10
134 15 N134S,
226 15 A226G, A226V,
205 12 c.612-2A>G, Y205X,
206 14
166 14 A166T,
179 13 R179Q, R179X,
172 6
185 9 A185T, A185V,
199 6 S199T,
165 12
180 12 G180V,
204 11 A204T, c.611+1G>A, c.611+3_611+4dupAA, A204V,
203 11
192 10
168 10
175 7 K175N,
202 7 I202T,
194 6
141 14 I141N, I141V,
188 6
167 13
178 13 A178G,
128 13 c.381dupT,
201 6
225 10 R225W, R225Q,
181 13
176 8
186 12
173 10
200 8
187 11 T187S, T187I,