SCN5A Variant M764T Detail

We estimate the penetrance of LQTS for SCN5A M764T around 5% and the Brugada syndrome penetrance around 51%. SCN5A M764T was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. M764T is not present in gnomAD. M764T has been functionally characterized in 0 papers. This residue is located in a 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 (5 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 M764T around 5% (0/10) and the Brugada syndrome penetrance around 51% (5/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.937 76 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 10 0 5 - -
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.

M764T has 53 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 11
723 9 I723V,
710 11
766 7
758 10 G758E,
769 10
773 11 P773S,
760 7 p.F760SfsX5,
780 12
776 7 p.Y776del,
765 5
759 9 c.2274delG, I759V, p.I759FfsX6,
792 12
764 0 M764R, M764K,
755 15
777 10 F777L,
791 13 L791F,
726 13
781 12 W781X,
720 11
788 9 I788V,
711 14
724 13 T724I,
782 7 N782T,
793 12 L793F,
820 13
713 12
762 6
727 13
767 5
770 10
756 13
814 12 R814Q,
722 13
813 14 c.2436+12G>A, c.2437-5C>A,
757 11
768 6
786 7
817 10 K817E,
761 6
779 13 Q779K, Q779X,
716 14
778 15
790 10
784 10 F784L,
763 5 E763D, E763K,
772 13 D772N,
771 10 L771V,
785 6 D785N,
783 10 I783T,
789 7 V789A, V789I,
714 10 V714A, V714D,
787 10