SCN5A Variant S199T Detail

We estimate the penetrance of LQTS for SCN5A S199T around 1% and the Brugada syndrome penetrance around 8%. SCN5A S199T was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. S199T is present in 1 alleles in gnomAD. S199T has been functionally characterized in 0 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 (0 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 S199T around 1% (0/11) and the Brugada syndrome penetrance around 8% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-0.61 0.951 -0.32 0.578 7 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
LITERATURE, COHORT, AND GNOMAD: - 1 1 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
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.

S199T has 45 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
223 12 V223L,
198 6
193 11 W193X, W193R,
209 15 N209T, N209S,
195 5
228 12 K228R,
227 12 L227P,
171 12
197 7
221 9
196 6
190 15 R190G, R190W, R190Q, R190L,
169 12
189 8
222 11 R222L, R222Q, R222X,
224 9 L224F,
191 12
226 13 A226V, A226G,
205 11 c.612-2A>G, Y205X,
206 10
217 12
172 11
185 12 A185V, A185T,
199 0 S199T,
165 13
204 9 c.611+1G>A, c.611+3_611+4dupAA, A204T, A204V,
203 6
208 14 E208K,
192 10
168 11
175 13 K175N,
202 5 I202T,
194 9
141 15 I141N, I141V,
188 11
201 6
219 15 R219C, c.656_657insATTCA, p.R219HfsX11, R219H,
225 9 R225Q, R225W,
218 11
176 14
207 12
186 14
200 4
187 14 T187I, T187S,
220 13 T220I,