SCN5A Variant c.5577_5578dupAA Detail

We estimate the penetrance of LQTS for SCN5A c.5577_5578dupAA around 3% and the Brugada syndrome penetrance around 57%. SCN5A c.5577_5578dupAA was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. c.5577_5578dupAA is not present in gnomAD. c.5577_5578dupAA 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 (5 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.5577_5578dupAA around 3% (0/11) and the Brugada syndrome penetrance around 57% (6/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 80 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 10 0 5 - -
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

c.5577_5578dupAA has 53 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
1814 13
1785 14
1794 13
1856 7
1853 11 I1853V,
1828 10 A1828S, A1828T,
1834 7 S1834R,
1818 10
1833 12 I1833M,
1866 10
1824 8 P1824A,
1838 7
1832 13 Q1832E,
1820 14 A1820V, A1820T,
1863 6
1501 14 p.L1501_K1505del, L1501V,
1860 0 c.5577_5578dupAA,
1857 6
1862 8
1867 11
1858 8
1829 14
1865 10
1835 9 L1835F,
1819 13 D1819N,
1786 12 L1786R, L1786Q, c.5356_5357delCT,
1861 6 V1861I, V1861F,
1864 5
1821 11
1815 13
1826 10 R1826C, R1826H,
1854 12
1825 8 L1825P,
1817 13
1877 15 E1877K,
1784 14 E1784K, E1784X,
1827 7
1839 11 D1839G,
1859 7
1791 15
1868 14
1852 14 D1852V,
1823 11 E1823K, p.E1823HfsX10,
1837 9
1831 10
1836 12 I1836T,
1497 15
1790 14 p.D1790del, D1790G, D1790N,
1494 15
1830 13
1840 11
1822 12 c.5464-5467delTCTG, c.5464_5467delTCTG,