SCN5A Variant I1563M Detail

We estimate the penetrance of LQTS for SCN5A I1563M around 9% and the Brugada syndrome penetrance around 17%. SCN5A I1563M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I1563M is not present in gnomAD. I1563M 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 I1563M around 9% (0/10) 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 0.84 16 9
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 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.

I1563M has 41 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 11 A1569P,
1544 6 T1544P,
270 15 Q270K,
1567 6 F1567L,
1536 14
1538 12
1566 6
1556 10
1568 9
1543 10 V1543A, V1543L,
1602 13
1558 10
1534 15
1542 12
1557 11 I1557V,
1562 6
1571 12 F1571C,
1572 15
1564 5
1570 11 p.I1570dup, p.1570_F1571insI, I1570V,
1546 13 M1546T,
1545 10
1626 11 R1626C, R1626L, R1626P, R1626H,
1606 13 T1606I,
1560 5 L1560F,
1559 6 I1559V,
1553 14 S1553R,
1539 13 C1539Y, C1539F,
1537 10
1565 7 L1565M,
1548 11 E1548K, G1548K,
1555 13 E1555K,
1605 15 c.4813+5insTGGG, c.4813+2_4813+5dupTGGG, c.4813+3_4813+6dupGGGT, G1605C, G1605D,
1547 11 V1547L,
1563 0
1541 8
1554 14
1540 9
1622 14
1561 6
1623 14 R1623Q, c.4867delC, R1623L, R1623X,