SCN5A Variant V909G Detail

We estimate the penetrance of LQTS for SCN5A V909G around 9% and the Brugada syndrome penetrance around 35%. SCN5A V909G was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V909G is not present in gnomAD. V909G 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 (3 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 V909G around 9% (0/10) and the Brugada syndrome penetrance around 35% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.923 47 7
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 12 0 3 - -
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.

V909G has 49 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
880 12
890 14 I890T,
901 13 E901K, S901L,
919 13
870 9
862 9
867 9 E867K, E867Q, E867X,
859 15
863 10
904 11 W904X,
864 6
871 8
909 0
876 11
857 13 G857D,
868 6 c.2602delC, L868X,
902 11
882 13
349 15 D349N,
881 10
860 12 p.L860fsx89,
911 7 G911E,
900 14
858 15 M858L,
872 12 D872N,
918 14
865 6
913 10
916 13
912 9 Q912R,
906 6
866 10 S866L, S866P,
351 14 G351D, G351C, G351V, G351S,
874 12 G874D,
910 4 S910L,
350 10 H350Q,
903 11 p.M903CfsX29,
877 10
879 15 W879R,
869 10 R869S,
905 7
352 12 Y352C,
915 9 C915R,
875 11
908 4
873 14 S873A,
914 11
861 9 c.2582_2583delTT, p.F861WfsX90,
907 8