SCN5A Variant L315M Detail

We estimate the penetrance of LQTS for SCN5A L315M around 2% and the Brugada syndrome penetrance around 47%. SCN5A L315M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L315M is not present in gnomAD. L315M has been functionally characterized in 0 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 L315M around 2% (0/10) and the Brugada syndrome penetrance around 47% (4/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.379 74 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 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.

L315M 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
300 15 V300I,
301 14
302 14
303 13
304 13
305 12 D305N,
306 11 L306V, L306F,
307 11
308 10
309 9 S309N, S309C,
310 8 D310N,
311 8
312 7 c.934+4C>T, E312K, c.934+1G>A,
313 5
314 4
315 0 L315P,
316 4
317 5 K317E, K317M, K317N,
318 7
319 8 G319C, G319S, G319R,
320 8 T320N,
321 9 S321Y,
322 10
323 11
324 11
325 12 L325R,
326 13
327 13
328 14
329 14
330 15 S330F,