SCN5A Variant V232A Detail

We estimate the penetrance of LQTS for SCN5A V232A around 5% and the Brugada syndrome penetrance around 16%. SCN5A V232A was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V232A is not present in gnomAD. V232A 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 V232A 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 0.891 15 3
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.

V232A has 43 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
848 11 I848F,
842 14
240 12 V240M,
231 4 c.692_693delCA,
131 12
193 13 W193R, W193X,
237 11
228 8 K228R,
138 7 M138I,
227 11 L227P,
143 14
137 11 I137V,
234 7 P234S,
142 10
197 15
229 6
845 11 c.2533delG,
232 0 V232F, V232I,
133 14
132 14 c.393-5C>A,
134 10 N134S,
849 15
226 11 A226G, A226V,
235 9 G235R, c.704-1G>C, c.703+1G>A,
840 12
843 14 T843A,
837 13
239 13 I239V, I239V ,
230 7 I230M, I230T, I230V,
139 10 p.I137_C139dup,
841 10 p.N841TfsX2, N841K,
236 8
847 14
136 13 L136P,
238 14
233 5
838 14
141 11 I141V, I141N,
135 9 M135V,
225 13 R225Q, R225W,
844 9 L844RfsX3,
145 14
140 13