SCN5A Variant E1574K Detail

We estimate the penetrance of LQTS for SCN5A E1574K around 3% and the Brugada syndrome penetrance around 67%. SCN5A E1574K was found in a total of 4 carriers in 3 papers and/or in gnomAD: 4 had Brugada syndrome, 0 had LQTS. E1574K is not present in gnomAD. E1574K has been functionally characterized in 4 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 E1574K around 3% (0/14) and the Brugada syndrome penetrance around 67% (9/14).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-3.61 0.981 -2.88 0.958 86 0
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
19029124 2009 1 0 1 0
26941339 2016 1 0 1 0
20129283 2010 4 0 4 0
LITERATURE, COHORT, AND GNOMAD: - 4 0 0 4 -
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.

Functional Data

Peak and late/persistent current are relative to wildtype (100% being no different from wildtype). V0.5 act/inact are the voltages at which half of the maximal current is reached during an activation and inactivation protocol, each is in units of mV and relative to wildtype.
PubMed ID Year Cell Type Peak Current (%WT) V1/2 Act. (mV) V1/2 Inact. (mV) Late/Persistent Current (%WT)
32533946 2020 HEK 43 9.8
19029124 2009
26941339 2016
20129283 2010

E1574K has 64 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 9 A1569P,
1525 9 V1525M, V1525A,
1524 10 I1524T,
1586 9
1567 11 F1567L,
1536 13
1538 10
1531 9
1566 13
1635 14
1568 10
1587 13 F1587V,
1602 13
1534 6
1601 15 L1601H,
1522 13
1575 4 C1575S,
1600 12
1571 5 F1571C,
1523 15 D1523N,
1521 11 I1521K, I1521T,
1527 12 K1527R,
1572 6
1570 7 p.1570_F1571insI, p.I1570dup, I1570V,
1529 12
1599 9
1526 13 T1526P,
1583 15 R1583C, R1583H,
1580 11
1630 14 I1630R, I1630V,
1532 12 V1532I, V1532F,
1626 13 R1626P, R1626C, R1626L, R1626H,
1603 14 I1603F,
1625 14
1576 7
1596 10 F1596C, F1596I,
1628 14
1589 12
1632 10 R1632L, R1632C, R1632H,
1539 14 C1539Y, C1539F,
1597 12 V1597M,
1530 7
1573 5
1535 9
1537 9
1594 13 F1594S,
1581 11 A1581S,
1591 13 W1591X,
1593 12 I1593M,
1595 7
1629 9 R1629Q, R1629X, R1629G,
1574 0 c.4719C>T, E1574K,
1533 10 T1533I,
1541 13
1592 8
1578 5 c.4732_4733dupAA,
1540 14
1528 15
1631 15 G1631D,
1590 14
1582 11 L1582P,
1579 9 L1579fsX53,
1598 10 V1598A,
1577 6