SCN5A Variant Q1613H Detail

We estimate the penetrance of LQTS for SCN5A Q1613H around 5% and the Brugada syndrome penetrance around 29%. SCN5A Q1613H was found in a total of 1 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. Q1613H is present in 1 alleles in gnomAD. Q1613H has been functionally characterized in 0 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 Q1613H around 5% (0/11) and the Brugada syndrome penetrance around 29% (3/11).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-2.44 0.864 -0.77 0.737 42 6
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 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.

Q1613H has 23 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
1606 13 T1606I,
1610 5 D1610G,
1615 7 Y1615X,
1612 5
1605 10 c.4813+3_4813+6dupGGGT, G1605C, c.4813+5insTGGG, G1605D, c.4813+2_4813+5dupTGGG,
1611 7 I1611V,
1616 6
1607 14
1620 12 T1620K, T1620M,
1617 8 p.F1617del,
1608 11
1604 10 V1604M, c.4810+3_4810+6dupGGGT,
1602 14
1622 12
1618 7
1614 5
1601 13 L1601H,
1621 13
1609 8 S1609L, S1609W,
1603 15 I1603F,
1623 14 R1623X, c.4867delC, R1623Q, R1623L,
1619 9 P1619L, c.4856delC, P1619Q,
1613 0 Q1613H, Q1613L,