SCN5A Variant L793F Detail

We estimate the penetrance of LQTS for SCN5A L793F around 4% and the Brugada syndrome penetrance around 8%. SCN5A L793F was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L793F is present in 1 alleles in gnomAD. L793F has been functionally characterized in 0 papers. This residue is located in a Non_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 (0 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 L793F around 4% (0/11) and the Brugada syndrome penetrance around 8% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.96 0.939 -0.79 0.845 2 3
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 15 0 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.

L793F has 41 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
758 9 G758E,
811 11 R811G, c.2435_2436+3delTGGTAinsCGCCT, R811H,
808 13 R808H, R808C, R808P,
760 11 p.F760SfsX5,
765 12
759 12 c.2274delG, I759V, p.I759FfsX6,
792 4
764 12 M764R, M764K,
755 13
791 7 L791F,
806 15 V806M,
800 10 R800H, R800L, R800C,
754 10
797 7 G797V,
801 13 M801V, p.801_803delMSN/insS,
750 14 Q750R,
788 9 I788V,
798 10
793 0 L793F,
762 12
810 12
756 13
814 12 R814Q,
807 10
813 14 c.2436+12G>A, c.2437-5C>A,
757 7
786 10
761 8
752 14 G752R,
809 14
790 6
784 15 F784L,
763 15 E763D, E763K,
796 6
785 13 D785N,
789 6 V789A, V789I,
753 12
795 7
799 11
787 11
794 6