21-34449528-C-T
Variant summary
Our verdict is Likely benign. Variant got -2 ACMG points: 0P and 2B. BP4_Moderate
The NM_000219.6(KCNE1):c.107G>A(p.Arg36His) variant causes a missense change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. 15/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_000219.6 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_benign. Variant got -2 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000248 AC: 2AN: 80688Hom.: 1 Cov.: 12
GnomAD3 exomes AF: 0.000135 AC: 34AN: 251362Hom.: 1 AF XY: 0.000147 AC XY: 20AN XY: 135884
GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.0000343 AC: 29AN: 846664Hom.: 13 Cov.: 23 AF XY: 0.0000428 AC XY: 18AN XY: 420998
GnomAD4 genome AF: 0.0000248 AC: 2AN: 80688Hom.: 1 Cov.: 12 AF XY: 0.0000507 AC XY: 2AN XY: 39430
ClinVar
Submissions by phenotype
not specified Uncertain:2
Variant classified as Uncertain Significance - Favor Pathogenic. The p.Arg36His variant in KCNE1 has been previously identified in 1 Caucasian individual with long QT syndrome (Napolitano 2005) and 1 individual with hearing loss by our laboratory. It has also been identified in 11/121094 of the total chromosomes across several populations by the Exome Aggregation Consortium (ExAC, http://exac.broadinstitute.org; dbSNP rs199473351). Computational prediction tools and conservation analysis suggest that the p.Arg36His variant may not impact the protein, though this information is not predictive enough to rule out pathogenicity. In summary, the clinical significance of the p.Arg36His variant is uncertain. ACMG/AMP criteria applied: PM2_Supporting, BP4. -
Variant summary: KCNE1 c.107G>A (p.Arg36His) results in a non-conservative amino acid change in the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 0.00014 in 251362 control chromosomes in the gnomAD database, including 1 homozygotes. The observed variant frequency is approximately 65 fold of the estimated maximal expected allele frequency for a pathogenic variant in KCNE1 causing Long QT Syndrome phenotype (2.1e-06). c.107G>A has been reported in the literature in individuals affected with Long QT Syndrome (Napolitano_2005, Lane_2018). These report(s) do not provide unequivocal conclusions about association of the variant with Long QT Syndrome. At least one publication reports experimental evidence evaluating an impact on protein function, suggesting that the variant results in a mild reduction in IKv7.1 current density in vitro (Lane_2018). The following publications have been ascertained in the context of this evaluation (PMID: 29625280, 16414944, 32451364). ClinVar contains an entry for this variant (Variation ID: 132650). Based on the evidence outlined above, the variant was classified as VUS-possibly benign. -
not provided Uncertain:2
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Published functional studies in cultured cells showed that, in the heterozygous state, p.(R36H) reduces the slow delayed rectifier potassium current density (Iks), supporting that this variant may have a loss of function effect (PMID: 29625280); In silico analysis indicates that this missense variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 30461122, 24710009, 28988457, 29625280, 17341399, 27965898, 34426522, 34667425, 16414944) -
Long QT syndrome Uncertain:1Benign:1
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Found in patient having exome sequencing for an unrelated indication. No known history of long QT syndrome. This interpretation considers GERP score and allele frequency data, in addition to published reports of the variant in the literature, available at the time of review. -
Cardiovascular phenotype Uncertain:1
The c.107G>A (p.R36H) alteration is located in exon 3 (coding exon 1) of the KCNE1 gene. This alteration results from a G to A substitution at nucleotide position 107, causing the arginine (R) at amino acid position 36 to be replaced by a histidine (H). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -
Long QT syndrome 5 Other:1
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Congenital long QT syndrome Other:1
This variant has been reported as associated with Long QT syndrome in the following publications (PMID:16414944). This is a literature report, and does not necessarily reflect the clinical interpretation of the Imperial College / Royal Brompton Cardiovascular Genetics laboratory. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at