SCN5A Variant A425P Detail

We estimate the penetrance of LQTS for SCN5A A425P around 25% and the Brugada syndrome penetrance around 6%. SCN5A A425P was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A425P is present in 1 alleles in gnomAD. A425P has been functionally characterized in 0 papers. This residue is located in a Non_Hotspot region for Brugada syndrome and a 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 (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A A425P around 25% (1/11) and the Brugada syndrome penetrance around 6% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.01 0.995 -2.6 0.594 2 41
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: - 1 1 0 0 -
VARIANT FEATURES ALONE: - 15 14 1 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.

A425P 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
410 15 A410V,
411 14 V411M,
412 14 V412D,
413 13 A413E, A413T,
414 13 M414V,
415 12 A415T,
416 11 Y416C,
417 11
418 10 E418K,
419 9 Q419X,
420 8
421 8
422 7
423 5
424 4 I424M,
425 0 A425T, A425P,
426 4
427 5
428 7 E428K,
429 8 E429K, p.E429del,
430 8 K430E,
431 9
432 10
433 11 R433C, R433S, R433H,
434 11
435 12
436 13
437 13 A437V,
438 14 M438L, M438T,
439 14 E439K, E439V,
440 15