NM_000492.4:c.3267G>C
Variant summary
Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3_Moderate
The NM_000492.4(CFTR):c.3267G>C(p.Trp1089Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,334 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).
Frequency
Consequence
NM_000492.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_pathogenic. Variant got 6 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
CFTR | NM_000492.4 | c.3267G>C | p.Trp1089Cys | missense_variant | Exon 20 of 27 | ENST00000003084.11 | NP_000483.3 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.00000658 AC: 1AN: 151916Hom.: 0 Cov.: 31
GnomAD3 exomes AF: 0.00000398 AC: 1AN: 251132Hom.: 0 AF XY: 0.00 AC XY: 0AN XY: 135720
GnomAD4 exome AF: 6.84e-7 AC: 1AN: 1461418Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0AN XY: 727014
GnomAD4 genome AF: 0.00000658 AC: 1AN: 151916Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0AN XY: 74198
ClinVar
Submissions by phenotype
Cystic fibrosis Uncertain:3
The p.W1089C variant (also known as c.3267G>C), located in coding exon 20 of the CFTR gene, results from a G to C substitution at nucleotide position 3267. The tryptophan at codon 1089 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
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not specified Uncertain:2
Variant summary: CFTR c.3267G>C (p.Trp1089Cys) results in a non-conservative amino acid change located in the ABC transporter type 1, transmembrane domain (IPR011527) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251132 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.3267G>C in the literature in individuals affected with Cystic Fibrosis and no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 28152038, 25880441). ClinVar contains an entry for this variant (Variation ID: 432801). Based on the evidence outlined above, the variant was classified as uncertain significance. -
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not provided Uncertain:2
The CFTR c.3267G>C; p.Trp1089Cys variant (rs150020260), to our knowledge, is not reported in the medical literature in association with disease, but is reported in ClinVar (Variation ID: 432801). This variant is only observed on one allele in the Genome Aggregation Database, indicating it is not a common polymorphism. The tryptophan at codon 1089 is highly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. Due to limited information, the clinical significance of the p.Trp1089Cys variant is uncertain at this time. -
The W1089C variant in the CFTR gene has not been reported previously as a pathogenic variant, nor as a benign variant, to our knowledge. The W1089C variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The W1089C variant is a non-conservative amino acid substitution, which is likely to impact secondary protein structure as these residues differ in polarity, charge, size and/or other properties. This substitution occurs at a position that is conserved across species. In silico analysis predicts this variant is probably damaging to the protein structure/function. We interpret W1089C as a variant of uncertain significance. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at