SCN5A Variant I1892N Detail

We estimate the penetrance of LQTS for SCN5A I1892N around 4% and the Brugada syndrome penetrance around 29%. SCN5A I1892N was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I1892N is not present in gnomAD. I1892N 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 I1892N around 4% (0/10) and the Brugada syndrome penetrance around 29% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.971 37 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: - 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.

I1892N 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
1877 15 E1877K,
1878 14
1879 14
1880 13 M1880V,
1881 13
1882 12
1883 11
1884 11 P1884L,
1885 10
1886 9
1887 8
1888 8
1889 7 Y1889C,
1890 5 E1890K,
1891 4
1892 0
1893 4 c.5676delC,
1894 5
1895 7 T1895I,
1896 8 L1896P, p.L1896PfsX47,
1897 8 R1897W, R1897Q, R1897Y,
1898 9 R1898H, R1898C,
1899 10
1900 11
1901 11 E1901K, E1901Q,
1902 12 E1902A,
1903 13 V1903M,
1904 13 S1904L,
1905 14
1906 14 M1906V, M1906T,
1907 15