SCN5A Variant p.1570_F1571insI Detail

We estimate the penetrance of LQTS for SCN5A p.1570_F1571insI around 1% and the Brugada syndrome penetrance around 50%. SCN5A p.1570_F1571insI was found in a total of 10 carriers in 3 papers and/or in gnomAD: 6 had Brugada syndrome, 0 had LQTS. p.1570_F1571insI is not present in gnomAD. p.1570_F1571insI has been functionally characterized in 3 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 p.1570_F1571insI around 1% (0/20) and the Brugada syndrome penetrance around 50% (10/20).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 59 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
16764707 2006 5 0 5 0
20031634 2009 10 0 6 0
19251209 2009 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 10 4 0 6 -
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.

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)
16764707 2006
20031634 2009
19251209 2009

p.1570_F1571insI has 47 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 4 A1569P,
1525 14 V1525A, V1525M,
1544 14 T1544P,
1524 13 I1524T,
1567 6 F1567L,
1536 11
1538 10
1531 13
1566 6
1568 6
1602 12
1534 7
1575 10 C1575S,
1562 14
1600 15
1571 5 F1571C,
1521 15 I1521T, I1521K,
1527 15 K1527R,
1572 6
1564 11
1570 0 I1570V, p.I1570dup, p.1570_F1571insI,
1529 13
1599 10
1532 13 V1532I, V1532F,
1626 13 R1626H, R1626P, R1626C, R1626L,
1603 14 I1603F,
1606 14 T1606I,
1576 10
1596 15 F1596C, F1596I,
1632 14 R1632C, R1632L, R1632H,
1539 13 C1539Y, C1539F,
1530 10
1573 6
1535 12
1537 7
1565 10 L1565M,
1595 12
1629 12 R1629Q, R1629G, R1629X,
1574 7 E1574K, c.4719C>T,
1533 10 T1533I,
1563 11
1541 11
1578 12 c.4732_4733dupAA,
1540 11
1598 12 V1598A,
1561 14
1577 11