SCN5A Variant T1026I Detail

We estimate the penetrance of LQTS for SCN5A T1026I around 6% and the Brugada syndrome penetrance around 6%. SCN5A T1026I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T1026I is not present in gnomAD. T1026I 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 T1026I around 6% (0/10) and the Brugada syndrome penetrance around 6% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.451 1 5
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 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.

T1026I 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
1011 15 P1011L, P1011S,
1012 14
1013 14
1014 13 P1014S,
1015 13 p.G1015DfsX14, E1015K,
1016 12 T1016M, c.3045_3046delGA,
1017 11
1018 11 K1018E,
1019 10
1020 9
1021 8 P1021S,
1022 8
1023 7 R1023C, R1023H, R1023P,
1024 5 K1024R,
1025 4 E1025A,
1026 0
1027 4 R1027Q, R1027W, R1027P,
1028 5
1029 7 E1029K,
1030 8
1031 8 p.G1031fsX27,
1032 9 E1032D, E1032K,
1033 10 Q1033R,
1034 11 P1034T,
1035 11 G1035V,
1036 12
1037 13
1038 13
1039 14
1040 14 G1040R,
1041 15 D1041N, D1041G,