NM_000492.4:c.1558G>T

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong

The NM_000492.4(CFTR):​c.1558G>T​(p.Val520Phe) variant causes a missense change. The variant allele was found at a frequency of 0.0000267 in 1,613,014 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 Pathogenic (★★★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000029 ( 0 hom. )

Consequence

CFTR
NM_000492.4 missense

Scores

11
7
1

Clinical Significance

Pathogenic reviewed by expert panel P:14

Conservation

PhyloP100: 4.96
Variant links:
Genes affected
CFTR (HGNC:1884): (CF transmembrane conductance regulator) This gene encodes a member of the ATP-binding cassette (ABC) transporter superfamily. The encoded protein functions as a chloride channel, making it unique among members of this protein family, and controls ion and water secretion and absorption in epithelial tissues. Channel activation is mediated by cycles of regulatory domain phosphorylation, ATP-binding by the nucleotide-binding domains, and ATP hydrolysis. Mutations in this gene cause cystic fibrosis, the most common lethal genetic disorder in populations of Northern European descent. The most frequently occurring mutation in cystic fibrosis, DeltaF508, results in impaired folding and trafficking of the encoded protein. Multiple pseudogenes have been identified in the human genome. [provided by RefSeq, Aug 2017]
CFTR-AS1 (HGNC:40144): (CFTR antisense RNA 1)

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 16 ACMG points.

PM1
In a domain ABC transporter 1 (size 223) in uniprot entity CFTR_HUMAN there are 54 pathogenic changes around while only 9 benign (86%) in NM_000492.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.988
PP5
Variant 7-117559629-G-T is Pathogenic according to our data. Variant chr7-117559629-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 7150.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr7-117559629-G-T is described in Lovd as [Pathogenic]. Variant chr7-117559629-G-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CFTRNM_000492.4 linkc.1558G>T p.Val520Phe missense_variant Exon 11 of 27 ENST00000003084.11 NP_000483.3 P13569-1A0A024R730
CFTR-AS1NR_149084.1 linkn.221+1104C>A intron_variant Intron 2 of 2

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CFTRENST00000003084.11 linkc.1558G>T p.Val520Phe missense_variant Exon 11 of 27 1 NM_000492.4 ENSP00000003084.6 P13569-1

Frequencies

GnomAD3 genomes
AF:
0.00000658
AC:
1
AN:
152036
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.00000398
AC:
1
AN:
251102
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135756
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000881
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000287
AC:
42
AN:
1460978
Hom.:
0
Cov.:
30
AF XY:
0.0000275
AC XY:
20
AN XY:
726852
show subpopulations
Gnomad4 AFR exome
AF:
0.0000299
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000342
Gnomad4 OTH exome
AF:
0.0000497
GnomAD4 genome
AF:
0.00000658
AC:
1
AN:
152036
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74260
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Alfa
AF:
0.0000167
Hom.:
2
Bravo
AF:
0.00000378
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:14
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Cystic fibrosis Pathogenic:7
Apr 25, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 520 of the CFTR protein (p.Val520Phe). This variant is present in population databases (rs77646904, gnomAD 0.002%). This missense change has been observed in individuals with cystic fibrosis (PMID: 1284466, 1376016, 22658665, 23974870). ClinVar contains an entry for this variant (Variation ID: 7150). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CFTR protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects CFTR function (PMID: 23891399, 23974870). For these reasons, this variant has been classified as Pathogenic. -

Jan 29, 2018
CFTR-France
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: curation

- -

Mar 17, 2017
CFTR2
Significance: Pathogenic
Review Status: reviewed by expert panel
Collection Method: research

- -

Dec 20, 2023
Ambry Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The c.1558G>T (p.V520F) alteration is located in exon 11 (coding exon 11) of the CFTR gene. This alteration results from a G to T substitution at nucleotide position 1558, causing the valine (V) at amino acid position 520 to be replaced by a phenylalanine (F). Based on data from gnomAD, the T allele has an overall frequency of 0.001% (2/282480) total alleles studied. The highest observed frequency was 0.002% (2/128982) of European (non-Finnish) alleles. This variant was first identified in 3 out of 42 cystic fibrosis chromosomes (Jones, 1992). Additionally, this variant is associated with elevated sweat chloride levels and pancreatic insufficiency (Sosnay, 2013). This amino acid position is well conserved in available vertebrate species. Functional studies found that this mutation results in very low levels of mature CFTR protein and little to no chloride conductance (Sosnay, 2013; Van Goor, 2014; Hirtz, 2004). This alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, this alteration is classified as pathogenic. -

Apr 01, 1992
OMIM
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: literature only

- -

Aug 13, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The CFTR c.1558G>T; p.Val520Phe variant (rs77646904, ClinVar Variation ID: 7150) is reported in over 100 cystic fibrosis individuals with an average sweat chloride of 101mEq/L and 92% of these individuals reported to be pancreatic insufficient (see CFTR2 database). This variant is only found on two alleles in the Genome Aggregation Database (v2.1.1), indicating it is not a common polymorphism. Computational analyses predict that this variant is deleterious (REVEL: 0.871). In support of these predictions, functional analyses demonstrate an effect of this variant on CFTR quantity and function (see CFTR2 database, Avramescu 2017, Van Goor 2014). Based on available information, this variant is considered to be pathogenic. References: Link to CFTR2 database: https://cftr2.org/ Avramescu RG et al. Mutation-specific downregulation of CFTR2 variants by gating potentiators. Hum Mol Genet. 2017 Dec 15;26(24):4873-4885. PMID: 29040544. Van Goor F et al. Effect of ivacaftor on CFTR forms with missense mutations associated with defects in protein processing or function. J Cyst Fibros. 2014 Jan;13(1):29-36. PMID: 23891399. -

Dec 04, 2019
Myriad Genetics, Inc.
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

NM_000492.3(CFTR):c.1558G>T(V520F) is classified as pathogenic in the context of cystic fibrosis and is associated with classic disease. Sources cited for classification include the following: PMID 1284466, 23974870 and 18456578. Classification of NM_000492.3(CFTR):c.1558G>T(V520F) is based on the following criteria: This is a well-established pathogenic variant in the literature that has been observed more frequently in patients with clinical diagnoses than in healthy populations. Please note: this variant was assessed in the context of healthy population screening. -

CFTR-related disorder Pathogenic:2
May 22, 2023
PreventionGenetics, part of Exact Sciences
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

The CFTR c.1558G>T variant is predicted to result in the amino acid substitution p.Val520Phe. This variant has been reported in multiple individuals with cystic fibrosis (see for example, Jones et al 1992. PubMed ID: 1284466; Van Goor et al 2013. PubMed ID: 23891399). An in vitro experimental study suggests this variant diminishes expression of the CFTR protein (Avramescu et al 2017. PubMed ID: 29040544). This variant is reported in 0.0016% of alleles in individuals of European (Non-Finnish) descent in gnomAD (http://gnomad.broadinstitute.org/variant/7-117199683-G-T) and has been interpreted by multiple laboratories in ClinVar as pathogenic (https://www.ncbi.nlm.nih.gov/clinvar/variation/7150/). This variant is interpreted as pathogenic. -

Mar 17, 2017
Natera, Inc.
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not provided Pathogenic:2
-
Joint Genome Diagnostic Labs from Nijmegen and Maastricht, Radboudumc and MUMC+
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance: Pathogenic
Review Status: no assertion criteria provided
Collection Method: clinical testing

- -

not specified Pathogenic:1
Sep 13, 2017
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

Variant summary: The CFTR c.1558G>T (p.Val520Phe) variant located in the P-loop containing nucleoside triphosphate hydrolase (via InterPro) involves the alteration of a conserved nucleotide and 5/5 in silico tools predict a damaging outcome for this variant. This variant was found in 2/276844 control chromosomes at a frequency of 0.0000072, which does not exceed the estimated maximal expected allele frequency of a pathogenic CFTR variant (0.0129603). The variant of interest has been reported in multiple affected CF pts (Sosnay_2013). A function study, Van Goor_2013, found the variant to significantly affect CFTR processing and Cl- transport. In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -

Cystic fibrosis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation Pathogenic:1
-
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Bronchiectasis with or without elevated sweat chloride 1 Pathogenic:1
Oct 04, 2023
Baylor Genetics
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.88
BayesDel_addAF
Pathogenic
0.42
D
BayesDel_noAF
Pathogenic
0.36
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.96
D;.;.;D;.
Eigen
Pathogenic
0.78
Eigen_PC
Pathogenic
0.72
FATHMM_MKL
Uncertain
0.97
D
LIST_S2
Pathogenic
0.98
D;D;D;D;D
M_CAP
Pathogenic
0.74
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D
MetaSVM
Pathogenic
0.89
D
MutationAssessor
Uncertain
2.3
M;.;.;.;.
PrimateAI
Uncertain
0.57
T
PROVEAN
Uncertain
-3.9
D;.;.;D;.
REVEL
Pathogenic
0.87
Sift
Uncertain
0.0010
D;.;.;D;.
Sift4G
Uncertain
0.0060
D;.;.;D;.
Polyphen
1.0
D;.;.;.;.
Vest4
0.95
MutPred
0.93
Gain of ubiquitination at K522 (P = 0.1096);.;.;.;.;
MVP
1.0
MPC
0.015
ClinPred
0.99
D
GERP RS
5.5
Varity_R
0.98
gMVP
0.98

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs77646904; hg19: chr7-117199683; API