SCN5A Variant L1654V Detail

We estimate the penetrance of LQTS for SCN5A L1654V around 53% and the Brugada syndrome penetrance around 17%. SCN5A L1654V was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L1654V is not present in gnomAD. L1654V has been functionally characterized in 0 papers. This residue is located in a Mild_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 (1 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 L1654V around 53% (2/10) and the Brugada syndrome penetrance around 17% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.832 17 72
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 12 2 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.

L1654V has 54 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 8
1659 9
404 13 L404Q, L404V,
1778 15
1773 14
1653 5
1771 10 I1771T,
401 14 S401P,
1652 8 M1652R, M1652T,
1634 13 L1634P,
1320 14 M1320I,
1650 7 L1650F,
260 15
1656 6
1477 15 K1477N,
1767 10 Y1767C,
1660 11 I1660V, I1660S,
1654 0
1648 10
1769 13
402 12 F402L,
1766 15 M1766V, M1766L, M1766T,
1319 12 G1319V,
1649 8 A1649V,
1768 14 I1768V,
1774 10 c.5321_5324dupACTT, N1774D,
1644 15 R1644C, R1644L, R1644H,
399 9
1657 6
1662 12
1317 14 F1317C,
1318 14
1772 14 L1772V,
1645 15 T1645M,
395 13
1323 14 V1323G,
394 15
1788 15 c.5361_5364delTGAG,
1770 10 I1770V,
1651 6
1591 15 W1591X,
1322 14 c.3963+4A>G, c.3963+2T>C,
407 13
1775 14 p.F1775LfsX15, F1775V,
1661 11 G1661R, G1661E,
1655 4
1631 15 G1631D,
406 13 N406K, N406S,
398 10
1647 10
400 12 G400R, G400E, G400A,
1646 12
1664 15
1658 5