SCN5A Variant V1861I Detail

We estimate the penetrance of LQTS for SCN5A V1861I around 0% and the Brugada syndrome penetrance around 41%. SCN5A V1861I was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. V1861I is not present in gnomAD. V1861I has been functionally characterized in 1 papers. This residue is located in a 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 (3 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 V1861I around 0% (0/11) and the Brugada syndrome penetrance around 41% (4/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-0.93 0.939 0.94 0.868 55 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
20129283 2010 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 12 0 3 - -
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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
20129283 2010

V1861I has 54 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
1855 10
1785 8
1794 12
1856 9
1853 12 I1853V,
1828 13 A1828T, A1828S,
1834 13 S1834R,
1818 12
1866 8
1824 5 P1824A,
1838 11
1820 15 A1820T, A1820V,
1863 6
1501 12 p.L1501_K1505del, L1501V,
1860 6 c.5577_5578dupAA,
1857 8
1862 4
1493 13 K1493R, K1493X, p.K1493del,
1867 11
1858 5
1865 6
1787 11 S1787N,
1835 14 L1835F,
1786 7 L1786Q, L1786R, c.5356_5357delCT,
1861 0 V1861F, V1861I,
1864 5
1821 11
1826 11 R1826H, R1826C,
1496 14
1854 11
1825 6 L1825P,
1793 14 M1793K,
1781 13 E1781G, E1781D,
1789 14
1817 14
1784 9 E1784X, E1784K,
1827 10
1498 12 M1498T, M1498V, M1498R,
1839 15 D1839G,
1788 15 c.5361_5364delTGAG,
1500 13 p.K1500del,
1859 7
1791 11
1868 12
1823 10 E1823K, p.E1823HfsX10,
1783 11
1837 14
1831 15
1497 11
1490 15
1790 10 D1790N, D1790G, p.D1790del,
1494 11
1822 11 c.5464_5467delTCTG, c.5464-5467delTCTG,
1782 12