SCN5A Variant p.F1617del Detail

We estimate the penetrance of LQTS for SCN5A p.F1617del around 55% and the Brugada syndrome penetrance around 13%. SCN5A p.F1617del was found in a total of 51 carriers in 10 papers and/or in gnomAD: 6 had Brugada syndrome, 29 had LQTS. p.F1617del is present in 5 alleles in gnomAD. p.F1617del has been functionally characterized in 12 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 p.F1617del around 55% (30/61) and the Brugada syndrome penetrance around 13% (7/61).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA None 20 39
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
10973849 2000 1 1 0 0
20541041 2010 1 1 0 0
25205533 2015 1 1 0 0
25236808 2014 4 1 0 0
26669661 2016 6 4 0 0
28782696 2017 41 25 5 3 CCD lots of overlaps
27566755 2016 5 5 0 0
17081365 2006 1 0 1 0
19716085 2009 1 1 0 0
30059973 2018 4 4 0 0
LITERATURE, COHORT, AND GNOMAD: - 51 16 29 6 -
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.

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)
10973849 2000
20541041 2010
25205533 2015
25236808 2014
26669661 2016
28782696 2017
15665061 2005
29017927 2017
27566755 2016
17081365 2006
19716085 2009
30059973 2018

p.F1617del has 36 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
271 15 L271V,
270 15 Q270K,
1627 15
1624 11 V1624I,
1568 14
1602 9
1601 5 L1601H,
1609 11 S1609L, S1609W,
1608 10
1613 8 Q1613L, Q1613H,
1600 10
1615 10 Y1615X,
1612 11
1564 15
1599 12
1626 12 R1626C, R1626L, R1626P, R1626H,
1603 10 I1603F,
1625 10
1606 10 T1606I,
1610 9 D1610G,
1596 14 F1596I, F1596C,
1597 10 V1597M,
1620 8 T1620K, T1620M,
1614 9
1619 6 P1619Q, P1619L, c.4856delC,
1605 7 c.4813+5insTGGG, c.4813+2_4813+5dupTGGG, c.4813+3_4813+6dupGGGT, G1605C, G1605D,
1611 12 I1611V,
1616 6
1607 12
1617 0 p.F1617del,
1604 6 V1604M, c.4810+3_4810+6dupGGGT,
1622 6
1618 4
1621 7
1598 10 V1598A,
1623 10 R1623X, R1623Q, R1623L, c.4867delC,