SCN5A Variant L306R Detail

We estimate the penetrance of LQTS for SCN5A L306R around 2% and the Brugada syndrome penetrance around 7%. SCN5A L306R was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L306R is not present in gnomAD. L306R 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 L306R around 2% (0/10) and the Brugada syndrome penetrance around 7% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.334 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.

L306R 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
291 15 p.N291TfsX52, N291K, N291S, N291H, p.N291_S293dup,
292 14 G292S,
293 14
294 13 V294M,
295 13 E295K,
296 12
297 11
298 11 G298D, G298S,
299 10 L299M, L299F,
300 9 V300I,
301 8
302 8
303 7
304 5
305 4 D305N,
306 0 L306F, L306V,
307 4
308 5
309 7 S309N, S309C,
310 8 D310N,
311 8
312 9 c.934+1G>A, E312K, c.934+4C>T,
313 10
314 11
315 11 L315P,
316 12
317 13 K317E, K317M, K317N,
318 13
319 14 G319R, G319S, G319C,
320 14 T320N,
321 15 S321Y,