SCN5A Variant L1601H Detail

We estimate the penetrance of LQTS for SCN5A L1601H around 3% and the Brugada syndrome penetrance around 14%. SCN5A L1601H was found in a total of 2 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. L1601H is present in 2 alleles in gnomAD. L1601H has been functionally characterized in 0 papers. This residue is located in a Mild_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 (1 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 L1601H around 3% (0/12) and the Brugada syndrome penetrance around 14% (1/12).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
-6.41 1 -4.03 0.971 12 2
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: - 2 2 0 0 -
VARIANT FEATURES ALONE: - 15 14 0 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.

L1601H has 46 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
1569 14 A1569P,
1627 13
1624 11 V1624I,
1568 11
1602 5
1601 0 L1601H,
1609 12 S1609L, S1609W,
1575 13 C1575S,
1608 10
1613 13 Q1613L, Q1613H,
1600 5
1571 12 F1571C,
1615 14 Y1615X,
1572 12
1564 13
1599 6
1626 9 R1626H, R1626P, R1626C, R1626L,
1603 6 I1603F,
1625 8
1606 9 T1606I,
1610 12 D1610G,
1596 9 F1596I, F1596C,
1628 13
1597 6 V1597M,
1620 11 T1620M, T1620K,
1565 14 L1565M,
1594 12 F1594S,
1614 14
1593 13 I1593M,
1595 11
1619 10 P1619Q, P1619L, c.4856delC,
1629 12 R1629X, R1629G, R1629Q,
1605 7 c.4813+2_4813+5dupTGGG, G1605C, c.4813+3_4813+6dupGGGT, c.4813+5insTGGG, G1605D,
1611 15 I1611V,
1574 15 c.4719C>T, E1574K,
1541 15
1616 9
1607 11
1592 15
1617 5 p.F1617del,
1604 5 c.4810+3_4810+6dupGGGT, V1604M,
1622 6
1618 8
1621 9
1598 6 V1598A,
1623 11 c.4867delC, R1623Q, R1623L, R1623X,