SCN5A Variant A770T Detail

We estimate the penetrance of LQTS for SCN5A A770T around 33% and the Brugada syndrome penetrance around 24%. SCN5A A770T was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A770T is not present in gnomAD. A770T has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a 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 (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A A770T around 33% (1/10) and the Brugada syndrome penetrance around 24% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.932 28 43
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 12 1 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.

A770T has 31 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
719 13
710 5
766 7
715 10 M715T, M715I,
713 9
712 10
762 12
774 12 Y774D, p.Y774TfsX28, Y774C, c.2320delT,
763 11 E763D, E763K,
778 13
767 6
772 7 D772N,
770 0
775 10
771 4 L771V,
720 14
785 15 D785N,
769 4
773 9 P773S,
714 7 V714A, V714D,
776 8 p.Y776del,
768 6
765 9
786 15
761 14
711 6
779 14 Q779K, Q779X,
764 10 M764R, M764K,
777 12 F777L,
782 12 N782T,
716 13