SCN5A Variant c.2582_2583delTT Detail

We estimate the penetrance of LQTS for SCN5A c.2582_2583delTT around 10% and the Brugada syndrome penetrance around 70%. SCN5A c.2582_2583delTT was found in a total of 11 carriers in 8 papers and/or in gnomAD: 11 had Brugada syndrome, 0 had LQTS. c.2582_2583delTT is not present in gnomAD. c.2582_2583delTT has been functionally characterized in 8 papers. This residue is located in a Hotspot region for Brugada syndrome and a Mild_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 (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A c.2582_2583delTT around 10% (1/21) and the Brugada syndrome penetrance around 70% (14/21).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 51 39
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
19251209 2009 1 0 1 0
19029124 2009 1 0 1 0
21273195 2011 7 0 7 0
22885917 2012 3 0 3 0
26921764 2016 1 0 1 0
26941339 2016 2 0 2 0
20129283 2010 11 0 11 0
29759671 2018 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 11 0 0 11 -
VARIANT FEATURES ALONE: - 15 11 1 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)
29759671 2018
19251209 2009
19029124 2009
21273195 2011
22885917 2012
26921764 2016
26941339 2016
20129283 2010

c.2582_2583delTT 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
891 11 I891N, I891T,
880 11
888 15
223 14 V223L,
856 8 V856L,
890 10 I890T,
901 15 E901K, S901L,
919 9
862 5
867 12 E867K, E867Q, E867X,
859 8
894 14 I894M,
863 8
904 14 W904X,
887 10
864 7
886 13 H886Q, H886P,
216 11 S216L, S216X,
221 12
909 9
852 14
854 10 c.2559delT,
876 14
857 5 G857D,
868 13 L868X, c.2602delC,
902 10
882 11
881 6
921 13
922 13 V922I,
860 4 p.L860fsx89,
911 10 G911E,
920 14
889 15
858 8 M858L,
217 12
918 8
855 10
917 11 L917R, L917V,
865 7
913 9
916 11
912 12 Q912R,
884 14
906 6
866 12 S866L, S866P,
910 6 S910L,
903 11 p.M903CfsX29,
853 11
219 13 R219C, p.R219HfsX11, R219H, c.656_657insATTCA,
877 13
879 15 W879R,
883 13
905 11
915 6 C915R,
215 13 p.L215CfsX10,
850 15 V850M, c.2549_2550insTG,
908 12
914 7
861 0 p.F861WfsX90, c.2582_2583delTT,
220 9 T220I,
907 10