SCN5A Variant G615E Detail

We estimate the penetrance of LQTS for SCN5A G615E around 11% and the Brugada syndrome penetrance around 2%. SCN5A G615E was found in a total of 77 carriers in 10 papers and/or in gnomAD: 1 had Brugada syndrome, 8 had LQTS. G615E is present in 66 alleles in gnomAD. G615E has been functionally characterized in 10 papers. This residue is located in a Non_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 (0 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A G615E around 11% (8/87) and the Brugada syndrome penetrance around 2% (2/87).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.11 0.975 0.06 0.626 2 21
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
24613995 2014 1 0 0 1 irritable bowel syndrome
11997281 2002 1 0 0 1 diLQT
18071069 2008 1 0 0 1 SCD
15840476 2005 1 1 0 0
23631430 2013 1 1 0 0
26669661 2016 2 1 0 0
26746457 2016 2 1 0 0
27566755 2016 2 2 0 0
19716085 2009 5 5 0 0
20129283 2010 1 0 1 0
LITERATURE, COHORT, AND GNOMAD: - 77 68 8 1 -
VARIANT FEATURES ALONE: - 15 14 0 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)
11997281 2002 HEK-tSA201 94 0.5 2.4
15840476 2005
24613995 2014 HEK 36 5.6 3.1 73
23631430 2013
18071069 2008 Xeno 100 -2.6 1.7
26669661 2016
26746457 2016
27566755 2016
19716085 2009
20129283 2010

G615E has 31 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
600 15
601 14 V601A,
602 14
603 13
604 13 L604V,
605 12 G605E,
606 11 A606T,
607 11 G607D, G607R, G607V,
608 10 D608H, D608N,
609 9
610 8 E610K,
611 8
612 7
613 5
614 4 P614S,
615 0 G615E,
616 4 S616N,
617 5
618 7 L618F,
619 8 L619F,
620 8 R620C, R620H,
621 9
622 10
623 11 M623T,
624 11 L624Q,
625 12 c.1872dupA, E625Q, E625D,
626 13
627 13 P627L,
628 14 P628R,
629 14 D629Y,
630 15 T630M,