SCN5A Variant V922I Detail

We estimate the penetrance of LQTS for SCN5A V922I around 7% and the Brugada syndrome penetrance around 7%. SCN5A V922I was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V922I is present in 1 alleles in gnomAD. V922I has been functionally characterized in 0 papers. This residue is located in a Non_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 (0 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 V922I around 7% (0/11) and the Brugada syndrome penetrance around 7% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-0.89 0.027 0.61 0.718 7 1
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: - 1 1 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
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.

V922I has 66 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 6 I891T, I891N,
848 13 I848F,
223 15 V223L,
856 11 V856L,
890 10 I890T,
901 15 S901L, E901K,
888 12
919 6
363 15
896 10 C896S,
895 7 L895F,
894 6 I894M,
247 14 V247L,
372 13
926 6
928 9 L928P,
925 6 I925F,
366 12
887 12
933 15
851 13 F851L, c.2552_2553dupGT, p.F851CfsX19, c.2550_2551dupGT,
897 9 G897R, G897E,
924 6 V924I,
927 8 N927K, N927S,
852 11
854 10 c.2559delT,
224 15 L224F,
860 14 p.L860fsx89,
845 13 c.2533delG,
857 11 G857D,
902 11
892 10 F892I,
881 13
849 8
898 12
893 11 R893H, R893C,
921 5
922 0 V922I,
920 7
889 13
900 12
930 10 c.2788-6C>T, c.2787+17_2787+18insACACACACACACACACACACACA,
1459 15 c.4376_4379delTCTT,
918 6
855 13
917 10 L917R, L917V,
916 11
929 10
906 13
408 15
847 12
846 10 L846R,
903 11 p.M903CfsX29,
367 15 R367H, R367L, R367C,
853 6
370 12 T370M,
923 5
915 11 C915R,
899 9
850 8 c.2549_2550insTG, V850M,
914 13
243 14
932 13
861 13 p.F861WfsX90, c.2582_2583delTT,
907 15
931 11