SCN5A Variant T1533I Detail

We estimate the penetrance of LQTS for SCN5A T1533I around 3% and the Brugada syndrome penetrance around 6%. SCN5A T1533I was found in a total of 2 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T1533I is present in 2 alleles in gnomAD. T1533I 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 T1533I around 3% (0/12) and the Brugada syndrome penetrance around 6% (0/12).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.08 0.02 1.31 0.616 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: - 2 2 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.

T1533I has 37 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
1569 14 A1569P,
1525 12 V1525A, V1525M,
1524 11 I1524T,
1567 12 F1567L,
1536 6
1538 10
1531 7
1566 13
1635 14
1568 15
1534 5
1575 14 C1575S,
1571 11 F1571C,
1527 9 K1527R,
1572 14
1570 10 p.1570_F1571insI, I1570V, p.I1570dup,
1529 5
1526 13 T1526P,
1630 14 I1630R, I1630V,
1532 4 V1532I, V1532F,
1632 12 R1632H, R1632C, R1632L,
1539 10 C1539Y, C1539F,
1530 6
1573 12
1535 7
1537 7
1633 13
1595 14
1636 11
1629 13 R1629G, R1629Q, R1629X,
1574 10 c.4719C>T, E1574K,
1533 0 T1533I,
1541 13
1578 13 c.4732_4733dupAA,
1540 10
1528 10
1577 13