SCN5A Variant T843K Detail

We estimate the penetrance of LQTS for SCN5A T843K around 46% and the Brugada syndrome penetrance around 24%. SCN5A T843K was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T843K is not present in gnomAD. T843K has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a 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 (2 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A T843K around 46% (2/10) 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 0.974 28 61
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 11 2 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.

T843K has 65 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
888 14
848 9 I848F,
896 14 C896S,
937 10
895 12 L895F,
839 6 L839P,
842 4
1457 13
240 13 V240M,
231 15 c.692_693delCA,
1455 8
1452 12
926 12
925 14 I925F,
227 15 L227P,
836 10 V836M,
234 12 P234S,
1451 11 V1451L, V1451D,
934 8
1458 13 S1458Y,
933 10
229 13
935 13 L935P,
851 13 p.F851CfsX19, c.2550_2551dupGT, c.2552_2553dupGT, F851L,
927 14 N927K, N927S,
852 14
845 6 c.2533delG,
232 14 V232F, V232I,
833 14 G833R,
892 12 F892I,
849 10
938 13
235 13 G235R, c.704-1G>C, c.703+1G>A,
840 4
843 0 T843A,
1456 11
930 9 c.2788-6C>T, c.2787+17_2787+18insACACACACACACACACACACACA,
1459 10 c.4376_4379delTCTT,
1460 11 F1460L,
837 9
239 10 I239V, I239V ,
1454 12
230 11 I230M, I230V, I230T,
242 14 A242D,
929 13
1448 14 I1448T, I1448L,
416 14 Y416C,
841 7 N841K, p.N841TfsX2,
236 13
847 7
941 15 S941N, S941F,
846 5 L846R,
936 13
238 13
233 10
838 8
853 15
844 5 L844RfsX3,
850 11 V850M, c.2549_2550insTG,
243 13
932 14
832 13
835 11 S835A, S835L,
931 10
1463 14 N1463Y,