SCN5A Variant A1649D Detail

We estimate the penetrance of LQTS for SCN5A A1649D around 55% and the Brugada syndrome penetrance around 45%. SCN5A A1649D was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. A1649D is not present in gnomAD. A1649D has been functionally characterized in 0 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 (4 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 A1649D around 55% (2/10) and the Brugada syndrome penetrance around 45% (4/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.972 65 75
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 9 2 4 - -
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.

A1649D has 61 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
403 10
414 13 M414V,
1643 10 I1643L,
404 12 L404V, L404Q,
1778 7
1773 10
1653 6
1771 8 I1771T,
1652 4 M1652T, M1652R,
1634 12 L1634P,
1777 8 V1777L, V1777M,
409 14 L409V, L409P,
1650 4 L1650F,
1656 11
1641 13
1477 13 K1477N,
1779 9 T1779M,
1776 9
1787 11 S1787N,
1767 13 Y1767C,
1654 8
1786 15 L1786R, L1786Q, c.5356_5357delCT,
1648 4
1769 12
1649 0 A1649V,
1768 14 I1768V,
1774 6 c.5321_5324dupACTT, N1774D,
1644 10 R1644L, R1644C, R1644H,
1640 14
256 13
399 14
405 15
1657 11
1496 14
1781 11 E1781G, E1781D,
1789 12
1772 10 L1772V,
1645 7 T1645M,
410 11 A410V,
1780 13 E1780G,
1788 10 c.5361_5364delTGAG,
1770 10 I1770V,
1658 13
1651 6
1500 14 p.K1500del,
1637 13
408 14
253 13
1792 14 D1792N, D1792Y, D1792V,
407 9
1775 6 p.F1775LfsX15, F1775V,
1642 11 G1642E,
1655 11
1790 14 D1790G, p.D1790del, D1790N,
406 12 N406K, N406S,
252 15
411 13 V411M,
1647 6
400 14 G400E, G400A, G400R,
1646 6
1782 12