SCN5A Variant V263A Detail

We estimate the penetrance of LQTS for SCN5A V263A around 20% and the Brugada syndrome penetrance around 9%. SCN5A V263A was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. V263A is not present in gnomAD. V263A has been functionally characterized in 0 papers. This residue is located in a Non_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 (0 diagnosed with Brugada syndrome) and 5 individuals for LQTS (1 with LQTS). These data combined with observations of carriers lead us to estimate the LQTS penetrance for SCN5A V263A around 20% (1/10) and the Brugada syndrome penetrance around 9% (0/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.972 1 24
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 1 0 - -
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.

V263A has 67 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
403 14
364 13
271 12 L271V,
266 6 L266H,
363 15
404 13 L404V, L404Q,
1544 13 T1544P,
270 11 Q270K,
1627 7
396 10 V396A, V396L,
1624 10 V1624I,
355 12 F355I, F355C,
1538 12
391 15
254 15
401 14 S401P,
1634 12 L1634P,
1543 11 V1543L, V1543A,
1542 7
361 11
260 6
366 13
365 9
258 9 V258A,
1546 9 M1546T,
369 12 M369K,
1545 10
1630 7 I1630R, I1630V,
1626 12 R1626P, R1626C, R1626L, R1626H,
267 6
1625 13
262 4 S262G,
357 15
256 11
399 11
272 14
397 14 I397F, I397T, I397V,
362 10
261 7
1628 8
1632 13 R1632L, R1632C, R1632H,
1539 11 C1539Y, C1539F,
392 11
255 13
269 11
395 10
393 14
1535 14
264 4
259 6
1633 11
1591 14 W1591X,
1548 15 E1548K, G1548K,
265 6 A265V,
358 10
263 0 V263I,
359 14 p.A359PfsX12, A359T,
1629 12 R1629Q, R1629X, R1629G,
1547 15 V1547L,
1541 12
1540 14
1631 9 G1631D,
368 13
268 9 G268S,
257 10
400 11 G400R, G400A, G400E,
1623 12 c.4867delC, R1623X, R1623Q, R1623L,