SCN5A Variant P1332L Detail

We estimate the penetrance of LQTS for SCN5A P1332L around 74% and the Brugada syndrome penetrance around 13%. SCN5A P1332L was found in a total of 7 carriers in 9 papers and/or in gnomAD: 1 had Brugada syndrome, 6 had LQTS. P1332L is not present in gnomAD. P1332L has been functionally characterized in 10 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 (1 diagnosed with Brugada syndrome) and 5 individuals for LQTS (2 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A P1332L around 74% (8/17) and the Brugada syndrome penetrance around 13% (2/17).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-9.74 1 -3.1 0.922 9 72
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
17698727 2007 2 2 0 0
15136511 2004 1 1 0 0 AV block
16244680 2005 1 1 0 0
18752142 2008 1 1 0 0
23631430 2013 1 1 0 0
24667783 2015 1 1 0 0
26940925 2016 1 1 0 0
20129283 2010 1 0 1 0
30059973 2018 1 1 0 0
LITERATURE, COHORT, AND GNOMAD: - 7 0 6 1 -
VARIANT FEATURES ALONE: - 15 12 2 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)
29791480 2018 CHO 104 -8.35 -9.84 267
15136511 2004
16244680 2005
18752142 2008
23631430 2013
24667783 2015
26940925 2016
20129283 2010
30059973 2018
17698727 2007 HEK 100 -5 -6.4 140

P1332L has 35 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
1328 8 V1328M,
1340 14 V1340I,
1757 13
1472 10 N1472S, p.N1472del,
1339 12 p.L1339del, L1339F,
1333 4
1471 13
1762 12 I1762M, p.I1762del,
1464 14 L1464P, c.4389_4396delCCTCTTTA,
944 14
1329 5 G1329S,
1766 14 M1766V, M1766L, M1766T,
1334 6 I1334V,
1473 14 F1473C, F1473S,
1341 15
1468 10 V1468A, V1468F,
1324 13
1327 9
1758 14 I1758V, p.I1758del,
1330 5 A1330D, A1330T, A1330P,
1338 10 L1338V,
1337 10
1326 10 A1326S,
1332 0 P1332L, P1332Q,
1465 12 p.F1465_L1480dup,
1467 14
1476 14 Q1476R, Q1476X,
1331 4 I1331V,
1761 14 L1761F, c.5280delG, L1761H,
1475 14 p.Q1475NfsX6, Q1475L,
1469 12 I1469V,
1336 7
824 13
1325 12 N1325S,
1335 5 M1335R,