SCN5A Variant L236Q Detail

We estimate the penetrance of LQTS for SCN5A L236Q around 20% and the Brugada syndrome penetrance around 22%. SCN5A L236Q was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L236Q is not present in gnomAD. L236Q 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 (2 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 L236Q around 20% (0/10) and the Brugada syndrome penetrance around 22% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.987 24 23
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 0 2 - -
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.

L236Q has 44 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
848 12 I848F,
937 14
839 13 L839P,
842 10
240 6 V240M,
231 6 c.692_693delCA,
193 11 W193X, W193R,
237 4
228 11 K228R,
138 14 M138I,
227 12 L227P,
836 15 V836M,
234 7 P234S,
933 13
229 10
245 14 Q245K,
845 9 c.2533delG,
232 8 V232I, V232F,
244 11
849 14
226 14 A226V, A226G,
420 13
241 8
235 4 c.703+1G>A, G235R, c.704-1G>C,
840 11
843 13 T843A,
419 11 Q419X,
930 14 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
423 12
837 11
239 6 I239V , I239V,
230 6 I230T, I230V, I230M,
242 10 A242D,
416 13 Y416C,
841 7 p.N841TfsX2, N841K,
236 0
847 14
846 14 L846R,
238 6
233 5
838 10
422 14
844 10 L844RfsX3,
243 10