rs1800085
Variant summary
Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PP2PP3_Moderate
The NM_000492.4(CFTR):c.964G>A(p.Val322Met) variant causes a missense change. The variant allele was found at a frequency of 0.0000576 in 1,613,894 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 (★★). Synonymous variant affecting the same amino acid position (i.e. V322V) has been classified as Likely benign.
Frequency
Consequence
NM_000492.4 missense
Scores
Clinical Significance
Conservation
Publications
- cystic fibrosisInheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Orphanet
- congenital bilateral absence of vas deferensInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- hereditary chronic pancreatitisInheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
Genome browser will be placed here
ACMG classification
Our verdict: Uncertain_significance. The variant received 5 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| CFTR | NM_000492.4 | c.964G>A | p.Val322Met | missense_variant | Exon 8 of 27 | ENST00000003084.11 | NP_000483.3 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| CFTR | ENST00000003084.11 | c.964G>A | p.Val322Met | missense_variant | Exon 8 of 27 | 1 | NM_000492.4 | ENSP00000003084.6 |
Frequencies
GnomAD3 genomes AF: 0.0000197 AC: 3AN: 152104Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.0000318 AC: 8AN: 251276 AF XY: 0.0000295 show subpopulations
GnomAD4 exome AF: 0.0000616 AC: 90AN: 1461790Hom.: 0 Cov.: 31 AF XY: 0.0000578 AC XY: 42AN XY: 727202 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.0000197 AC: 3AN: 152104Hom.: 0 Cov.: 32 AF XY: 0.0000269 AC XY: 2AN XY: 74296 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not specified Uncertain:2
The Val322Met variant in CFTR has been reported in one French individual with cy stic fibrosis and was absent from at least 8 control chromosomes (Le Marechal 20 01); it is unclear from this report if this individual carried any other variant s in CFTR. This variant has also been reported in dbSNP without frequency inform ation (rs1800085). Valine (Val) at position 322 is well conserved in mammals and chicken, but not in more distantly related species, and computational analyses (PolyPhen2, SIFT, AlignGVGD) do not provide strong evidence for or against patho genicity. In summary, additional information is required to assess the clinical significance of this variant. -
Variant summary: CFTR c.964G>A (p.Val322Met) results in a conservative amino acid change located in the ABC transporter type 1, transmembrane domain (IPR011527) of the encoded protein sequence. Three of five 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 251276 control chromosomes (gnomAD). c.964G>A has been reported in the literature as a non-informative genotype (exact zygosity/second allele is not specified) in an individual with Cystic Fibrosis (LeMarechal_2001) and in an individual with congenital unilateral absence of vas deferens (CUAVD) with azoospermia (Mieusset_2019). These report(s) do not provide unequivocal conclusions about association of the variant with Cystic Fibrosis. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in approximately 17% of normal chloride channel conductance relative to wild type (Bihler_2024). ClinVar contains an entry for this variant (Variation ID: 43580). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -
Cystic fibrosis Uncertain:2
The p.V322M variant (also known as c.964G>A), located in coding exon 8 of the CFTR gene, results from a G to A substitution at nucleotide position 964. The valine at codon 322 is replaced by methionine, an amino acid with highly similar properties. This variant was reported in one individual with cystic fibrosis; however, limited details were provided regarding clinical phenotype and it is uncertain whether additional CFTR alterations were detected (Le Maréchal C et al. Hum. Genet., 2001 Apr;108:290-8). This alteration was also detected in one male with congenital unilateral absence of the vas deferens; however, the presence of a second CFTR variant is unknown (Mieusset R et al. Andrology, 2020 05;8:645-653). Based on structural analysis, the variant is predicted to be structurally damaging because it changes in cavity/pocket size (Ittisoponpisan S et al. J Endocr Soc, 2018 Aug;2:842-854). This amino acid position is well 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. -
This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 322 of the CFTR protein (p.Val322Met). This variant is present in population databases (rs1800085, gnomAD 0.009%). This missense change has been observed in individual(s) with cystic fibrosis (PMID: 11379874). ClinVar contains an entry for this variant (Variation ID: 43580). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on CFTR protein function. 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. -
CFTR-related disorder Uncertain:1
- -
not provided Uncertain:1
PM2 -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at