SCN5A Variant c.2559delT Detail

We estimate the penetrance of LQTS for SCN5A c.2559delT around 8% and the Brugada syndrome penetrance around 52%. SCN5A c.2559delT was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. c.2559delT is not present in gnomAD. c.2559delT 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 (4 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.2559delT around 8% (0/11) and the Brugada syndrome penetrance around 52% (5/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 70 10
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
26921764 2016 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 11 0 4 - -
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)
26921764 2016

c.2559delT has 68 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 6 I891T, I891N,
880 12
888 7
848 10 I848F,
223 9 V223L,
856 6 V856L,
890 8 I890T,
919 11
862 11
896 15 C896S,
859 10
895 12 L895F,
894 11 I894M,
1447 13
149 10
147 15
926 13
925 13 I925F,
227 13 L227P,
887 5
1451 15 V1451D, V1451L,
886 10 H886P, H886Q,
851 6 c.2550_2551dupGT, F851L, c.2552_2553dupGT, p.F851CfsX19,
221 12
852 6
854 0 c.2559delT,
222 13 R222L, R222X, R222Q,
224 12 L224F,
845 14 c.2533delG,
857 5 G857D,
150 14
902 13
882 12
892 11 F892I,
881 8
849 9
226 12 A226V, A226G,
893 13 R893H, R893C,
921 13
922 10 V922I,
860 10 p.L860fsx89,
889 9
858 6 M858L,
144 14
217 15
918 10
855 4
865 13
148 10
884 6
906 13
885 10
146 14 V146A, V146M,
847 10
846 12 L846R,
152 12 D152N,
853 6
219 13 p.R219HfsX11, R219H, c.656_657insATTCA, R219C,
151 12
879 14 W879R,
923 14
883 10
915 13 C915R,
850 6 c.2549_2550insTG, V850M,
914 14
145 11
861 10 p.F861WfsX90, c.2582_2583delTT,
220 11 T220I,