SCN5A Variant K237M Detail

We estimate the penetrance of LQTS for SCN5A K237M around 30% and the Brugada syndrome penetrance around 19%. SCN5A K237M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. K237M is not present in gnomAD. K237M has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (1 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 K237M around 30% (1/10) and the Brugada syndrome penetrance around 19% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.949 19 38
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 13 1 1 - -
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.

K237M has 39 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
842 13
240 6 V240M,
231 9 c.692_693delCA,
193 11 W193X, W193R,
418 13 E418K,
237 0
228 13 K228R,
227 14 L227P,
234 10 P234S,
933 14
229 14
246 14
245 12 Q245K,
845 12 c.2533delG,
232 11 V232I, V232F,
244 10
415 13 A415T,
191 14
420 11
241 7
235 6 c.703+1G>A, c.704-1G>C, G235R,
840 14
419 8 Q419X,
423 9
837 14
239 8 I239V, I239V ,
230 10 I230M, I230V, I230T,
242 9 A242D,
416 12 Y416C,
841 11 p.N841TfsX2, N841K,
236 4
192 14
238 6
233 10
838 13
422 11
421 14
844 14 L844RfsX3,
243 11