SCN5A Variant Q912H Detail

We estimate the penetrance of LQTS for SCN5A Q912H around 26% and the Brugada syndrome penetrance around 15%. SCN5A Q912H was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. Q912H is not present in gnomAD. Q912H has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (1 diagnosed with Brugada syndrome) and 5 individuals for LQTS (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A Q912H around 26% (1/10) and the Brugada syndrome penetrance around 15% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.83 14 32
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 1 1 - -
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.

Q912H has 42 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
364 14
919 12
363 11
360 8
356 15 D356N,
361 14
904 9 W904X,
864 13
354 14
909 9
868 14 c.2602delC, L868X,
902 13
349 15 D349N,
357 13
860 14 p.L860fsx89,
362 14
911 4 G911E,
920 13
900 13
918 12
917 10 L917R, L917V,
865 14
913 5
916 7
912 0 Q912R,
347 14
906 8
351 10 G351S, G351C, G351D, G351V,
910 7 S910L,
350 11 H350Q,
903 9 p.M903CfsX29,
346 15 E346G, E346K, E346X, E346D,
359 10 p.A359PfsX12, A359T,
905 11
352 7 Y352C,
915 7 C915R,
899 14
908 9
914 8
861 12 p.F861WfsX90, c.2582_2583delTT,
353 13 T353I,
907 4