SCN5A Variant G926V Detail

We estimate the penetrance of LQTS for SCN5A G926V around 6% and the Brugada syndrome penetrance around 27%. SCN5A G926V was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. G926V is not present in gnomAD. G926V has been functionally characterized in 0 papers. This residue is located in a Mild_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 (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 G926V around 6% (0/10) and the Brugada syndrome penetrance around 27% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.926 34 4
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.

G926V has 72 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 9 I891N, I891T,
848 11 I848F,
890 14 I890T,
888 13
919 12
896 9 C896S,
937 15
895 5 L895F,
842 11
894 9 I894M,
247 11 V247L,
240 14 V240M,
1455 14
254 15
372 15
926 0
250 13
409 12 L409P, L409V,
928 6 L928P,
925 4 I925F,
227 15 L227P,
366 14
934 11
1458 14 S1458Y,
933 9
246 11
935 12 L935P,
851 14 c.2550_2551dupGT, c.2552_2553dupGT, F851L, p.F851CfsX19,
412 11 V412D,
897 10 G897R, G897E,
924 6 V924I,
927 4 N927S, N927K,
852 12
854 13 c.2559delT,
845 10 c.2533delG,
244 14
1418 14
892 10 F892I,
849 7
898 13
893 13 R893H, R893C,
921 9
922 6 V922I,
405 12
241 15
920 11
843 12 T843A,
930 5 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
1459 11 c.4376_4379delTCTT,
918 12
917 15 L917R, L917V,
239 13 I239V , I239V,
1454 14
230 15 I230T, I230V, I230M,
242 13 A242D,
929 5
413 15 A413T, A413E,
408 11
847 10
846 7 L846R,
936 14
853 9
370 13 T370M,
923 6
899 12
844 14 L844RfsX3,
850 8 V850M, c.2549_2550insTG,
411 14 V411M,
243 10
932 8
931 6
1463 14 N1463Y,