SCN5A Variant I1452M Detail

We estimate the penetrance of LQTS for SCN5A I1452M around 6% and the Brugada syndrome penetrance around 36%. SCN5A I1452M was found in a total of 0 carriers in 0 papers and/or in gnomAD: 0 had Brugada syndrome, 0 had LQTS. I1452M is not present in gnomAD. I1452M has been functionally characterized in 0 papers. This residue is located in a 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 (3 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 I1452M around 6% (0/10) and the Brugada syndrome penetrance around 36% (3/10).

In Silico Data

PROVEAN PolyPhen-2 BLAST-PSSM REVEL Penetrance Density BrS (%) Penetrance Density LQT3 (%)
NA NA NA 0.61 52 4
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 12 0 3 - -
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.

I1452M has 56 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
888 12
1355 13
896 14 C896S,
895 14 L895F,
839 14 L839P,
1352 13
1445 13 Y1445H,
1457 9
1453 6
1455 6
1447 9
1444 15 L1444I,
1351 10 M1351V, M1351R,
1449 6 Y1449S, Y1449C,
1452 0
1461 13 T1461S,
812 13 L812Q,
1350 14 I1350T, I1350L,
1344 12 F1344S, F1344L,
806 15 V806M,
1450 7
1451 4 V1451L, V1451D,
934 15
1458 11 S1458Y,
1348 7 F1348L,
1349 13
1346 15 L1346I, L1346P,
1418 14
892 11 F892I,
1356 14 c.4066_4068delTT,
1462 15
1412 12 L1412F,
810 15
840 14
889 13
843 12 T843A,
1456 6
1459 10 c.4376_4379delTCTT,
1460 12 F1460L,
816 14 F816L, F816Y,
1425 13
813 15 c.2436+12G>A, c.2437-5C>A,
1454 7
1446 10
1448 6 I1448L, I1448T,
809 13
1421 14
885 14
847 13
1345 13 W1345C,
846 13 L846R,
1416 12 c.4245+2T>A, A1416G, c.4245+1G>C, A1416E, c.4245+1G>A,
1347 11
1415 12
844 14 L844RfsX3,
1428 15 A1428S, A1428V,