SCN5A Variant L920F Detail

We estimate the penetrance of LQTS for SCN5A L920F around 5% and the Brugada syndrome penetrance around 23%. SCN5A L920F was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L920F is not present in gnomAD. L920F has been functionally characterized in 0 papers. This residue is located in a Mild_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 (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 L920F around 5% (0/10) and the Brugada syndrome penetrance around 23% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.718 29 2
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.

L920F has 66 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
364 12
891 12 I891T, I891N,
856 14 V856L,
890 14 I890T,
901 15 E901K, S901L,
919 6
363 9
896 14 C896S,
404 15 L404V, L404Q,
895 12 L895F,
360 13
894 9 I894M,
247 14 V247L,
254 12
372 12
926 11
371 15 Q371E,
250 14
928 10 L928P,
925 9 I925F,
361 14
904 12 W904X,
366 7
365 13
258 13 V258A,
897 11 G897E, G897R,
924 7 V924I,
927 11 N927S, N927K,
369 12 M369K,
857 14 G857D,
902 11
373 15
849 14
898 13
893 14 R893H, R893C,
921 5
922 7 V922I,
405 14
362 10
860 15 p.L860fsx89,
261 13
920 0
900 10
930 15 c.2787+17_2787+18insACACACACACACACACACACACA, c.2788-6C>T,
918 6
917 5 L917V, L917R,
913 12
916 6
912 13 Q912R,
929 13
906 12
408 14
903 8 p.M903CfsX29,
367 11 R367H, R367C, R367L,
359 13 A359T, p.A359PfsX12,
853 11
370 10 T370M,
923 6
915 9 C915R,
368 14
899 7
850 15 V850M, c.2549_2550insTG,
914 11
257 13
861 14 c.2582_2583delTT, p.F861WfsX90,
907 11