SCN5A Variant M1545I Detail

We estimate the penetrance of LQTS for SCN5A M1545I around 19% and the Brugada syndrome penetrance around 15%. SCN5A M1545I was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. M1545I is not present in gnomAD. M1545I 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 (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 M1545I around 19% (0/10) and the Brugada syndrome penetrance around 15% (1/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.95 12 22
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.

M1545I has 63 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
271 11 L271V,
266 6 L266H,
1544 5 T1544P,
270 6 Q270K,
1627 7
1567 11 F1567L,
1624 10 V1624I,
1536 15
1552 14 Q1552R, Q1552L,
355 14 F355C, F355I,
1549 11
1538 10
1566 14
1556 13
1568 13
356 13 D356N,
1543 7 V1543L, V1543A,
1602 14
1542 6
1557 12 I1557V,
361 13
1562 15
1571 13 F1571C,
1564 9
1546 6 M1546T,
1545 0
1630 11 I1630R, I1630V,
1626 7 R1626L, R1626H, R1626C, R1626P,
267 9
1550 14
1625 12
1560 9 L1560F,
262 11 S262G,
357 12
272 14
273 11
1559 13 I1559V,
1628 12
1539 10 C1539F, C1539Y,
269 8
1620 12 T1620M, T1620K,
1537 12
1565 14 L1565M,
264 13
259 14
1548 6 G1548K, E1548K,
265 10 A265V,
1619 12 P1619Q, c.4856delC, P1619L,
358 10
263 10 V263I,
359 14 p.A359PfsX12, A359T,
1629 12 R1629Q, R1629X, R1629G,
1547 7 V1547L,
1563 10
1541 6
1540 10
268 10 G268S,
1622 10
1618 15
1621 14
1598 13 V1598A,
1561 11
1623 7 R1623Q, R1623L, R1623X, c.4867delC,