rs200204024
Variant summary
Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM1PP2BP4
The NM_000492.4(CFTR):c.1950C>A(p.Phe650Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000867 in 1,613,968 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. F650F) has been classified as Likely benign.
Frequency
Consequence
NM_000492.4 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Our verdict: Uncertain_significance. The variant received 2 ACMG points.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
---|---|---|---|---|---|---|---|---|
CFTR | NM_000492.4 | c.1950C>A | p.Phe650Leu | missense_variant | Exon 14 of 27 | ENST00000003084.11 | NP_000483.3 |
Ensembl
Frequencies
GnomAD3 genomes AF: 0.0000263 AC: 4AN: 152092Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.0000319 AC: 8AN: 251026 AF XY: 0.0000295 show subpopulations
GnomAD4 exome AF: 0.00000684 AC: 10AN: 1461758Hom.: 0 Cov.: 31 AF XY: 0.00000825 AC XY: 6AN XY: 727180 show subpopulations
GnomAD4 genome AF: 0.0000263 AC: 4AN: 152210Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1AN XY: 74414 show subpopulations
ClinVar
Submissions by phenotype
Cystic fibrosis Uncertain:5
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The p.F650L variant (also known as c.1950C>A), located in coding exon 14 of the CFTR gene, results from a C to A substitution at nucleotide position 1950. The phenylalanine at codon 650 is replaced by leucine, an amino acid with highly similar properties. This variant was described in an individual with bronchiectasis and normal sweat chloride concentration (Ziedalski TM et al, Chest 2006 Oct; 130(4):995-1002). This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Based on the available evidence, the clinical significance of this variant remains unclear. -
This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -
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This sequence change replaces phenylalanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 650 of the CFTR protein (p.Phe650Leu). This variant is present in population databases (rs200204024, gnomAD 0.04%). This missense change has been observed in individual(s) with bronchiectasis (PMID: 17035430). ClinVar contains an entry for this variant (Variation ID: 550836). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt CFTR protein function with a positive predictive value of 80%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
not specified Uncertain:1
Variant summary: CFTR c.1950C>A (p.Phe650Leu) results in a non-conservative amino acid change located in the CFTR regulator domain (IPR025837) of the encoded protein sequence. Four of four in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 251026 control chromosomes, predominantly at a frequency of 0.00044 within the East Asian subpopulation in the gnomAD database. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1950C>A has been reported in the literature in one individual with bronchiectasis who had normal sweat chloride levels (Ziedalski_2006). It has also been reported in individuals with unrelated/unspecified phenotypes (e.g. Qiu_2017, Ni_2022). These report(s) do not provide unequivocal conclusions about association of the variant with Cystic Fibrosis. To our knowledge, 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: 17035430, 28027573, 35313924). ClinVar contains an entry for this variant (Variation ID: 550836). Based on the evidence outlined above, the variant was classified as uncertain significance. -
CFTR-related disorder Uncertain:1
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Cystic fibrosis;C0238339:Hereditary pancreatitis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation;C2749757:Bronchiectasis with or without elevated sweat chloride 1 Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at