SCN5A Variant G837A Detail

We estimate the penetrance of LQTS for SCN5A G837A around 15% and the Brugada syndrome penetrance around 24%. SCN5A G837A was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. G837A is not present in gnomAD. G837A has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (2 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 G837A around 15% (0/10) and the Brugada syndrome penetrance around 24% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.904 29 16
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 13 0 2 - -
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.

G837A 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
937 10
839 6 L839P,
842 9
240 14 V240M,
231 15 c.692_693delCA,
1455 15
237 14
836 4 V836M,
234 7 P234S,
934 12
933 14
845 12 c.2533delG,
830 14
232 13 V232F, V232I,
833 8 G833R,
940 13 S940N,
831 12
420 13
938 13
235 8 G235R, c.704-1G>C, c.703+1G>A,
840 5
942 14
843 9 T843A,
1456 15
419 15 Q419X,
423 14
834 8 N834D,
1460 14 F1460L,
837 0
239 10 I239V, I239V ,
230 14 I230M, I230V, I230T,
416 13 Y416C,
841 5 N841K, p.N841TfsX2,
236 11
847 15
941 11 S941N, S941F,
846 14 L846R,
936 14
238 10
233 9
838 3
844 9 L844RfsX3,
829 14
832 10
835 5 S835A, S835L,