SCN5A Variant p.L860fsx89 Detail

We estimate the penetrance of LQTS for SCN5A p.L860fsx89 around 11% and the Brugada syndrome penetrance around 52%. SCN5A p.L860fsx89 was found in a total of 1 carriers in 1 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. p.L860fsx89 is not present in gnomAD. p.L860fsx89 has been functionally characterized in 1 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 (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 p.L860fsx89 around 11% (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 69 14
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
16764707 2006 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)
16764707 2006

p.L860fsx89 has 59 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 13 I891T, I891N,
880 14
223 11 V223L,
856 6 V856L,
890 13 I890T,
919 11
862 7
867 13 E867K, E867X, E867Q,
859 5
863 9
887 12
864 9
216 8 S216L, S216X,
851 14 c.2552_2553dupGT, F851L, p.F851CfsX19, c.2550_2551dupGT,
221 9
909 12
852 12
854 10 c.2559delT,
222 13 R222Q, R222X, R222L,
224 13 L224F,
857 5 G857D,
902 14
882 12
881 9
921 13
922 14 V922I,
860 0 p.L860fsx89,
911 12 G911E,
920 15
214 14
858 8 M858L,
217 8
918 8
855 9
917 11 L917R, L917V,
865 11
913 9
916 13
148 14
912 14 Q912R,
884 14
906 10
866 14 S866P, S866L,
910 9 S910L,
203 14
903 14 p.M903CfsX29,
853 11
219 10 R219H, c.656_657insATTCA, R219C, p.R219HfsX11,
151 15
218 11
883 14
905 15
915 8 C915R,
215 10 p.L215CfsX10,
850 15 c.2549_2550insTG, V850M,
914 6
861 4 c.2582_2583delTT, p.F861WfsX90,
220 6 T220I,
907 13