SCN5A Variant A1640P Detail

We estimate the penetrance of LQTS for SCN5A A1640P around 11% and the Brugada syndrome penetrance around 21%. SCN5A A1640P was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A1640P is not present in gnomAD. A1640P has been functionally characterized in 0 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 (2 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 A1640P around 11% (0/10) and the Brugada syndrome penetrance around 21% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.976 23 11
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
LITERATURE, COHORT, AND GNOMAD: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 13 0 2 - -
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.

A1640P 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
1643 6 I1643L,
1778 15
249 13 K249X,
1635 14
254 14
1634 11 L1634P,
250 14
1641 5
1639 3 G1639A,
1779 15 T1779M,
1787 14 S1787N,
1648 13
1649 14 A1649V,
1644 7 R1644L, R1644H, R1644C,
1640 0
256 11
1793 14 M1793K,
1789 11
255 10
1645 8 T1645M,
251 11
1638 9 R1638X, R1638Q,
259 14
1633 12
1637 6
253 11
1636 10
1823 14 E1823K, p.E1823HfsX10,
1642 5 G1642E,
1790 14 D1790N, D1790G, p.D1790del,
252 7
1647 10
257 15
1822 14 c.5464-5467delTCTG, c.5464_5467delTCTG,
1646 10
1782 13