SCN5A Variant A838S Detail

We estimate the penetrance of LQTS for SCN5A A838S around 16% and the Brugada syndrome penetrance around 29%. SCN5A A838S was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A838S is not present in gnomAD. A838S 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 A838S around 16% (0/10) and the Brugada syndrome penetrance around 29% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.818 39 18
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.

A838S has 56 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 15 I848F,
939 13 L939F,
937 7
839 5 L839P,
842 6
240 12 V240M,
231 15 c.692_693delCA,
1455 14
237 13
836 6 V836M,
234 8 P234S,
417 14
934 9
933 10
935 13 L935P,
845 11 c.2533delG,
830 15
232 14 V232I, V232F,
833 9 G833R,
940 10 S940N,
831 11
420 10
938 10
241 13
235 8 c.703+1G>A, c.704-1G>C, G235R,
840 5
942 12
843 8 T843A,
1456 14
419 13 Q419X,
930 13 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
1459 15 c.4376_4379delTCTT,
423 13
834 9 N834D,
1460 12 F1460L,
837 3
239 8 I239V, I239V ,
230 13 I230M, I230V, I230T,
242 12 A242D,
416 10 Y416C,
413 15 A413T, A413E,
841 5 p.N841TfsX2, N841K,
236 10
847 14
941 9 S941F, S941N,
846 13 L846R,
936 11
238 8
233 10
838 0
844 10 L844RfsX3,
829 15
243 13
832 10
835 5 S835L, S835A,
931 14