SCN5A Variant I1524V Detail

We estimate the penetrance of LQTS for SCN5A I1524V around 24% and the Brugada syndrome penetrance around 12%. SCN5A I1524V was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I1524V is not present in gnomAD. I1524V has been functionally characterized in 0 papers. This residue is located in a Mild_Hotspot region for Brugada syndrome and a Mild_Hotspot region for LQTS. In silico predictions, functional data (if available), and location in structure are equivalent to phenotyping 10 individuals for Brugada syndrome (1 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 I1524V around 24% (1/10) and the Brugada syndrome penetrance around 12% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.424 11 31
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 13 1 1 - -
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.

I1524V has 38 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
1525 5 V1525A, V1525M,
1524 0 I1524T,
1512 11 R1512L, R1512W, R1512Q,
1586 14
1518 11
1531 9
1534 11
1522 7
1575 12 C1575S,
1510 13
1571 15 F1571C,
1523 5 D1523N,
1521 5 I1521K, I1521T,
1527 5 K1527R,
1572 14
1570 13 p.1570_F1571insI, I1570V, p.I1570dup,
1529 8
1526 6 T1526P,
1583 15 R1583C, R1583H,
1580 10
1532 12 V1532I, V1532F,
1576 10
1517 12
1519 8
1530 6
1573 10
1535 14
1581 9 A1581S,
1513 13
1520 7
1574 10 E1574K, c.4719C>T,
1533 11 T1533I,
1592 15
1578 9 c.4732_4733dupAA,
1528 10
1582 11 L1582P,
1579 12 L1579fsX53,
1577 6