SCN5A Variant P877H Detail

We estimate the penetrance of LQTS for SCN5A P877H around 4% and the Brugada syndrome penetrance around 54%. SCN5A P877H was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. P877H is not present in gnomAD. P877H has been functionally characterized in 0 papers. This residue is located in a 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 (5 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 P877H around 4% (0/10) and the Brugada syndrome penetrance around 54% (5/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.935 81 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: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 10 0 5 - -
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.

P877H has 54 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
891 15 I891N, I891T,
880 5
890 10 I890T,
901 10 S901L, E901K,
870 12
862 12
867 14 E867X, E867Q, E867K,
1430 14 D1430N,
1426 11
1444 14 L1444I,
1440 8 W1440X,
863 15
1429 14
904 14 W904X,
887 12
864 12
886 9 H886Q, H886P,
871 9
909 10
1423 13 D1423H,
876 4
1422 12 M1422R,
857 15 G857D,
868 12 L868X, c.2602delC,
902 10
882 10
881 9
893 12 R893H, R893C,
889 12
900 14
858 14 M858L,
872 11 D872N,
1425 14
865 7
906 11
866 11 S866L, S866P,
874 8 G874D,
910 14 S910L,
878 6 R878C, R878L, R878H,
885 15
350 13 H350Q,
903 14 p.M903CfsX29,
1441 11 E1441Q,
877 0
879 6 W879R,
869 11 R869S,
883 11
905 7
915 15 C915R,
875 7
908 11
873 12 S873A,
861 13 c.2582_2583delTT, p.F861WfsX90,
907 14