SCN5A Variant A1924S Detail

We estimate the penetrance of LQTS for SCN5A A1924S around 3% and the Brugada syndrome penetrance around 14%. SCN5A A1924S was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A1924S is not present in gnomAD. A1924S 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 (1 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 A1924S around 3% (0/10) and the Brugada syndrome penetrance around 14% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.702 13 0
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 14 0 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.

A1924S 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
1909 15 Q1909R,
1910 14 R1910K,
1911 14
1912 13
1913 13 R1913S, R1913C, R1913H,
1914 12 R1914G,
1915 11 H1915Q, H1915Y, H1915N, H1915P,
1916 11
1917 10
1918 9
1919 8 R1919H, R1919C,
1920 8 S1920C,
1921 7
1922 5 K1922R, K1922N,
1923 4 H1923D, H1923Y,
1924 0 A1924T,
1925 4 S1925F, p.S1925CfsX20,
1926 5
1927 7 L1927P,
1928 8 F1928V,
1929 8 R1929H, R1929C,
1930 9 Q1930H,
1931 10
1932 11 A1932V,
1933 11 G1933D, G1933A, G1933V,
1934 12
1935 13 G1935S,
1936 13
1937 14 S1937A,
1938 14 E1938X, E1938K,
1939 15 p.E1939_E1943del,