SCN5A Variant T1549K Detail

We estimate the penetrance of LQTS for SCN5A T1549K around 5% and the Brugada syndrome penetrance around 29%. SCN5A T1549K was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. T1549K is not present in gnomAD. T1549K 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 (2 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 T1549K around 5% (0/10) and the Brugada syndrome penetrance around 29% (2/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.818 39 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: - 0 0 0 0 -
VARIANT FEATURES ALONE: - 15 13 0 2 - -
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.

T1549K 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
277 11
271 14 L271V,
266 12 L266H,
276 14 L276P, L276Q,
1544 12 T1544P,
270 10 Q270K,
360 12
1552 5 Q1552R, Q1552L,
355 12 F355I, F355C,
1549 0
1556 9
356 6 D356N,
1543 13 V1543A, V1543L,
1558 14
1557 10 I1557V,
361 12
343 12
354 11
1546 10 M1546T,
1545 11
267 15
1550 5
1560 11 L1560F,
357 6
272 13
274 10 G274C,
273 7
1559 13 I1559V,
1553 9 S1553R,
269 8
345 15
275 13 N275K,
347 14
1548 5 G1548K, E1548K,
351 15 G351D, G351C, G351V, G351S,
1555 13 E1555K,
265 13 A265V,
358 10
1551 7 D1551N, D1551Y,
359 11 A359T, p.A359PfsX12,
1547 7 V1547L,
1554 11
344 15 A344S,
268 12 G268S,
1561 15
1623 14 R1623L, R1623X, R1623Q, c.4867delC,