SCN5A Variant T902I Detail

We estimate the penetrance of LQTS for SCN5A T902I around 6% and the Brugada syndrome penetrance around 43%. SCN5A T902I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T902I is not present in gnomAD. T902I 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 (4 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 T902I around 6% (0/10) and the Brugada syndrome penetrance around 43% (4/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.816 64 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: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 11 0 4 - -
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.

T902I has 76 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 15
891 9 I891N, I891T,
880 10
888 13
856 14 V856L,
890 6 I890T,
901 5 E901K, S901L,
919 7
862 13
363 13
896 12 C896S,
895 13 L895F,
894 7 I894M,
372 10
904 7 W904X,
366 14
887 10
864 14
886 12 H886Q, H886P,
376 14 R376H, R376C,
871 14
897 10 G897R, G897E,
909 11
1423 15 D1423H,
854 13 c.2559delT,
876 13
1422 11 M1422R,
857 12 G857D,
1418 15
902 0
882 14
892 12 F892I,
349 13 D349N,
373 11
881 9
898 8
893 7 R893H, R893C,
921 14
922 11 V922I,
860 14 p.L860fsx89,
911 13 G911E,
920 11
889 11
900 6
858 14 M858L,
918 10
1425 15
917 13 L917R, L917V,
865 10
913 14
916 11
912 13 Q912R,
906 6
351 15 G351V, G351D, G351S, G351C,
910 12 S910L,
878 11 R878L, R878C, R878H,
1421 13
350 10 H350Q,
903 5 p.M903CfsX29,
367 12 R367L, R367C, R367H,
853 13
370 14 T370M,
877 10
879 8 W879R,
923 11
883 15
905 6
352 13 Y352C,
915 8 C915R,
899 7
850 15 c.2549_2550insTG, V850M,
908 10
914 13
861 10 p.F861WfsX90, c.2582_2583delTT,
353 14 T353I,
907 9