SCN5A Variant c.5464_5467delTCTG Detail

We estimate the penetrance of LQTS for SCN5A c.5464_5467delTCTG around 4% and the Brugada syndrome penetrance around 32%. SCN5A c.5464_5467delTCTG was found in a total of 4 carriers in 2 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. c.5464_5467delTCTG is not present in gnomAD. c.5464_5467delTCTG has been functionally characterized in 2 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 (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 c.5464_5467delTCTG around 4% (0/14) and the Brugada syndrome penetrance around 32% (4/14).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 39 6
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
17897635 2007 6 0 0 3 Conduction defects
20129283 2010 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 4 3 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)
17897635 2007 HEK 1 300
20129283 2010

c.5464_5467delTCTG has 50 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
1814 14
1785 14
1794 9
1856 14
1853 14 I1853V,
1795 12 Y1795N, Y1795C, p.Y1795_E1796insD, Y1795H,
1828 10 A1828T, A1828S,
1818 9
1801 13
1824 6 P1824A,
1820 7 A1820V, A1820T,
1641 10
1860 12 c.5577_5578dupAA,
1857 11
1862 15
1639 12 G1639A,
1858 12
1829 14
1787 11 S1787N,
1819 9 D1819N,
1786 10 c.5356_5357delCT, L1786R, L1786Q,
1861 11 V1861I, V1861F,
1864 13
1821 4
1815 14
1644 14 R1644L, R1644C, R1644H,
1640 14
1798 13 W1798X,
1826 5 R1826H, R1826C,
1854 13
1825 5 L1825P,
1797 8 I1797V,
1800 13
1793 6 M1793K,
1789 9
1817 10
1645 15 T1645M,
1827 9
1796 11
1799 15
1788 13 c.5361_5364delTGAG,
1638 11 R1638X, R1638Q,
1791 10
1792 11 D1792N, D1792V, D1792Y,
1823 5 E1823K, p.E1823HfsX10,
1816 13 D1816E, D1816N, c.5445_5446insT,
1831 14
1790 7 D1790G, D1790N, p.D1790del,
1822 0 c.5464-5467delTCTG, c.5464_5467delTCTG,
1782 14