SCN5A Variant V929M Detail

We estimate the penetrance of LQTS for SCN5A V929M around 19% and the Brugada syndrome penetrance around 28%. SCN5A V929M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V929M is not present in gnomAD. V929M 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 V929M around 19% (0/10) and the Brugada syndrome penetrance around 28% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.889 35 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.

V929M has 68 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
414 13 M414V,
891 15 I891N, I891T,
848 14 I848F,
896 13 C896S,
404 13 L404V, L404Q,
937 13
895 10 L895F,
842 11
249 11 K249X,
894 13 I894M,
247 7 V247L,
240 11 V240M,
254 12
926 5
250 9
409 9 L409P, L409V,
928 5 L928P,
925 6 I925F,
934 11
933 6
246 6
935 10 L935P,
412 6 V412D,
897 14 G897R, G897E,
924 6 V924I,
927 7 N927K, N927S,
245 11 Q245K,
845 11 c.2533delG,
244 10
415 11 A415T,
849 10
921 11
922 10 V922I,
405 11
248 12
938 15
241 11
920 13
843 13 T843A,
419 15 Q419X,
930 4 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
1459 13 c.4376_4379delTCTT,
1772 15 L1772V,
239 10 I239V, I239V ,
251 13
410 11 A410V,
242 9 A242D,
929 0
416 11 Y416C,
413 10 A413T, A413E,
408 8
253 13
847 14
407 12
846 10 L846R,
936 11
238 14
853 13
370 14 T370M,
923 9
406 13 N406S, N406K,
850 13 c.2549_2550insTG, V850M,
411 9 V411M,
243 6
932 6
257 15
931 7
1463 14 N1463Y,