SCN5A Variant K1527R Detail

We estimate the penetrance of LQTS for SCN5A K1527R around 7% and the Brugada syndrome penetrance around 44%. SCN5A K1527R was found in a total of 1 carriers in 2 papers and/or in gnomAD: 1 had Brugada syndrome, 0 had LQTS. K1527R is not present in gnomAD. K1527R has been functionally characterized in 2 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 (3 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 K1527R around 7% (0/11) and the Brugada syndrome penetrance around 44% (4/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
0.24 0.077 -1.44 0.568 60 3
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
28341781 2017 1 0 1 0
15851320 2005 2 0 1 1
LITERATURE, COHORT, AND GNOMAD: - 1 0 0 1 -
VARIANT FEATURES ALONE: - 15 12 0 3 - -
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)
28341781 2017
15851320 2005

K1527R has 32 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
1525 7 V1525A, V1525M,
1524 5 I1524T,
1512 14 R1512W, R1512Q, R1512L,
1536 15
1531 7
1635 15
1534 11
1522 10
1510 15
1523 7 D1523N,
1521 10 I1521K, I1521T,
1527 0 K1527R,
1570 15 p.1570_F1571insI, I1570V, p.I1570dup,
1529 4
1526 6 T1526P,
1580 15
1532 9 V1532F, V1532I,
1576 15
1519 12
1800 15
1530 6
1573 14
1535 13
1581 13 A1581S,
1520 11
1636 14
1574 12 c.4719C>T, E1574K,
1533 9 T1533I,
1578 11 c.4732_4733dupAA,
1528 6
1582 14 L1582P,
1577 10