SCN5A Variant V146L Detail

We estimate the penetrance of LQTS for SCN5A V146L around 3% and the Brugada syndrome penetrance around 9%. SCN5A V146L was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V146L is not present in gnomAD. V146L has been functionally characterized in 0 papers. This residue is located in a Non_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 (0 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 V146L around 3% (0/10) and the Brugada syndrome penetrance around 9% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.712 3 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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 15 0 0 - -
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.

V146L has 41 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
888 15
154 14 P154L,
848 13 I848F,
223 12 V223L,
153 12
149 5
147 6
164 11 F164L,
138 13 M138I,
143 5
142 7
156 14 W156X, W156R,
229 13
163 15 c.486delC,
851 10 c.2552_2553dupGT, c.2550_2551dupGT, F851L, p.F851CfsX19,
852 13
854 14 c.2559delT,
222 13 R222L, R222X, R222Q,
155 13
150 6
157 12 T157I,
160 11 p.V160fs,
226 12 A226G, A226V,
858 14 M858L,
144 6
855 11
139 11 p.I137_C139dup,
148 7
884 10
885 13
146 0 V146M, V146A,
847 14
152 11 D152N,
141 10 I141N, I141V,
161 13 E161Q, E161K,
225 14 R225Q, R225W,
151 9
159 15 Y159C, Y159X,
883 14
145 5
140 10