SCN5A Variant H1915Q Detail

We estimate the penetrance of LQTS for SCN5A H1915Q around 5% and the Brugada syndrome penetrance around 8%. SCN5A H1915Q was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. H1915Q is present in 1 alleles in gnomAD. H1915Q 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 H1915Q around 5% (0/11) and the Brugada syndrome penetrance around 8% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-5.22 0.999 -0.94 0.835 1 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.

H1915Q has 31 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
1900 15
1901 14 E1901K, E1901Q,
1902 14 E1902A,
1903 13 V1903M,
1904 13 S1904L,
1905 12
1906 11 M1906T, M1906V,
1907 11
1908 10 I1908V,
1909 9 Q1909R,
1910 8 R1910K,
1911 8
1912 7
1913 5 R1913H, R1913S, R1913C,
1914 4 R1914G,
1915 0 H1915Y, H1915Q, H1915N, H1915P,
1916 4
1917 5
1918 7
1919 8 R1919C, R1919H,
1920 8 S1920C,
1921 9
1922 10 K1922R, K1922N,
1923 11 H1923D, H1923Y,
1924 11 A1924T,
1925 12 p.S1925CfsX20, S1925F,
1926 13
1927 13 L1927P,
1928 14 F1928V,
1929 14 R1929C, R1929H,
1930 15 Q1930H,