SCN5A Variant A1856T Detail

We estimate the penetrance of LQTS for SCN5A A1856T around 7% and the Brugada syndrome penetrance around 24%. SCN5A A1856T was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A1856T is not present in gnomAD. A1856T 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 A1856T around 7% (0/10) and the Brugada syndrome penetrance around 24% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.965 28 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.

A1856T has 62 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
1850 10 C1850S,
1855 4
1814 11
1785 15
1794 11
1849 12 H1849R,
1856 0
1853 6 I1853V,
1795 14 Y1795N, Y1795H, Y1795C, p.Y1795_E1796insD,
1828 15 A1828S, A1828T,
1834 10 S1834R,
1818 11
1833 14 I1833M,
1880 12 M1880V,
1866 14
1824 12 P1824A,
1838 5
1832 14 Q1832E,
1504 15 K1504E,
1811 14 Y1811X, Y1811N,
1863 11
1851 10 M1851V, M1851I,
1501 9 p.L1501_K1505del, L1501V,
1860 7 c.5577_5578dupAA,
1857 4
1874 15
1862 10
1858 6
1865 14
1835 9 L1835F,
1786 12 L1786R, L1786Q, c.5356_5357delCT,
1861 9 V1861I, V1861F,
1864 12
1815 14
1821 12
1798 14 W1798X,
1826 14 R1826C, R1826H,
1854 7
1825 9 L1825P,
1848 11
1817 12
1877 12 E1877K,
1827 10
1498 11 M1498R, M1498T, M1498V,
1839 6 D1839G,
1500 14 p.K1500del,
1859 5
1876 13
1791 12
1852 7 D1852V,
1502 13 G1502S, G1502A,
1842 14 M1842T, M1842V, M1842L,
1837 10
1831 13
1836 12 I1836T,
1497 12
1790 14 p.D1790del, D1790G, D1790N,
1809 14 I1809M,
1494 12
1841 10
1840 7
1822 14 c.5464-5467delTCTG, c.5464_5467delTCTG,