SCN5A Variant L304V Detail

We estimate the penetrance of LQTS for SCN5A L304V around 2% and the Brugada syndrome penetrance around 10%. SCN5A L304V was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L304V is not present in gnomAD. L304V 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 L304V around 2% (0/10) and the Brugada syndrome penetrance around 10% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.387 7 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.

L304V has 31 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
289 15 G289S,
290 14 p.T290_G292del,
291 14 p.N291TfsX52, N291K, N291S, N291H, p.N291_S293dup,
292 13 G292S,
293 13
294 12 V294M,
295 11 E295K,
296 11
297 10
298 9 G298D, G298S,
299 8 L299M, L299F,
300 8 V300I,
301 7
302 5
303 4
304 0
305 4 D305N,
306 5 L306F, L306V,
307 7
308 8
309 8 S309N, S309C,
310 9 D310N,
311 10
312 11 c.934+1G>A, E312K, c.934+4C>T,
313 11
314 12
315 13 L315P,
316 13
317 14 K317E, K317M, K317N,
318 14
319 15 G319R, G319S, G319C,