SCN5A Variant F1486L Detail

We estimate the penetrance of LQTS for SCN5A F1486L around 71% and the Brugada syndrome penetrance around 7%. SCN5A F1486L was found in a total of 1 carriers in 3 papers and/or in gnomAD: 0 had Brugada syndrome, 1 had LQTS. F1486L is not present in gnomAD. F1486L has been functionally characterized in 5 papers. This residue is located in a Non_Hotspot region for Brugada syndrome and a 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 (3 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A F1486L around 71% (4/11) and the Brugada syndrome penetrance around 7% (0/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-5.58 0.092 2.18 0.962 1 87
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
17210841 2007 1 0 0 1 SIDS
22360817 2012 1 1 0 0
30059973 2018 1 1 0 0
LITERATURE, COHORT, AND GNOMAD: - 1 0 1 0 -
VARIANT FEATURES ALONE: - 15 12 3 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.

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)
17210841 2007 tsA201 100 3.7 14.3 518
30059973 2018
22360817 2012
17646591 2007
20038812 2010 DRG 8 320

F1486L has 27 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
1875 12 M1875T, M1875K, p.M1875dup,
1872 14 K1872N,
1496 13
1474 15
1491 6 Q1491H,
1481 12 G1481V, G1481R, G1481E,
1874 13
1493 11 p.K1493del, K1493R, K1493X,
1484 8
1486 0 p.F1486del, F1486L,
1478 11 K1478E,
1488 6 T1488R,
1475 14 Q1475L, p.Q1475NfsX6,
1490 9
1498 15 M1498V, M1498T, M1498R,
1483 6 Q1483H,
1485 4
1494 11
1487 7 M1487L, M1487K,
1495 10 Y1495S,
1869 14
1876 14
1479 15
1482 10
1489 9 E1489D,
1492 8
1868 15