SCN5A Variant F1775V Detail

We estimate the penetrance of LQTS for SCN5A F1775V around 27% and the Brugada syndrome penetrance around 19%. SCN5A F1775V was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. F1775V is present in 1 alleles in gnomAD. F1775V 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 (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A F1775V around 27% (1/11) and the Brugada syndrome penetrance around 19% (2/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-6.47 0.952 -2.62 0.966 20 40
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: - 1 1 0 0 -
VARIANT FEATURES ALONE: - 15 12 1 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.

F1775V has 71 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 12
414 7 M414V,
939 14 L939F,
1785 15
1643 11 I1643L,
404 12 L404V, L404Q,
1778 6
1773 8
249 11 K249X,
1653 10
254 15
1771 7 I1771T,
1652 9 M1652R, M1652T,
1777 7 V1777L, V1777M,
418 13 E418K,
250 12
409 9 L409V, L409P,
1650 8 L1650F,
1656 15
1641 14
417 13
1477 14 K1477N,
246 13
1779 6 T1779M,
412 10 V412D,
935 15 L935P,
1493 14 K1493R, p.K1493del, K1493X,
1470 13
245 15 Q245K,
1776 5
1787 13 S1787N,
1767 14 Y1767C,
1654 14
1648 10
1769 11
415 11 A415T,
1649 6 A1649V,
1768 12 I1768V,
1774 7 N1774D, c.5321_5324dupACTT,
1473 14 F1473S, F1473C,
1644 13 R1644L, R1644C, R1644H,
256 14
405 13
1657 14
1474 13
1781 10 E1781D, E1781G,
1772 6 L1772V,
1645 8 T1645M,
251 15
410 5 A410V,
1780 9 E1780G,
1788 14 c.5361_5364delTGAG,
1770 11 I1770V,
1651 12
416 15 Y416C,
413 9 A413T, A413E,
408 10
253 11
407 7
1783 12
936 14
1775 0 p.F1775LfsX15, F1775V,
1642 10 G1642E,
406 10 N406S, N406K,
252 13
411 7 V411M,
932 14
1647 10
1646 6
1489 15 E1489D,
1782 10