rs397508418

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1PP2PP3_Moderate

The NM_000492.4(CFTR):​c.266A>G​(p.Tyr89Cys) variant causes a missense change. The variant allele was found at a frequency of 0.0000143 in 1,534,370 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

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

CFTR
NM_000492.4 missense

Scores

11
5
3

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:7O:1

Conservation

PhyloP100: 5.48

Publications

6 publications found
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 Gene-Disease associations (from GenCC):
  • cystic fibrosis
    Inheritance: 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 deferens
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
  • hereditary chronic pancreatitis
    Inheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

PM1
In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 25 uncertain in NM_000492.4
PP2
Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 197 curated pathogenic missense variants (we use a threshold of 10). The gene has 46 curated benign missense variants. Gene score misZ: -3.1397 (below the threshold of 3.09). Trascript score misZ: -1.0868 (below the threshold of 3.09). GenCC associations: The gene is linked to hereditary chronic pancreatitis, cystic fibrosis, congenital bilateral absence of vas deferens.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.904

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CFTRNM_000492.4 linkc.266A>G p.Tyr89Cys missense_variant Exon 3 of 27 ENST00000003084.11 NP_000483.3 P13569-1A0A024R730

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CFTRENST00000003084.11 linkc.266A>G p.Tyr89Cys missense_variant Exon 3 of 27 1 NM_000492.4 ENSP00000003084.6 P13569-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152164
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000483
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:
0.00
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.00000798
AC:
2
AN:
250722
AF XY:
0.00
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000145
AC:
20
AN:
1382206
Hom.:
0
Cov.:
23
AF XY:
0.0000130
AC XY:
9
AN XY:
692562
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
32002
American (AMR)
AF:
0.0000224
AC:
1
AN:
44634
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
25678
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39280
South Asian (SAS)
AF:
0.00
AC:
0
AN:
84712
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52988
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5580
European-Non Finnish (NFE)
AF:
0.0000183
AC:
19
AN:
1039720
Other (OTH)
AF:
0.00
AC:
0
AN:
57612
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.453
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152164
Hom.:
0
Cov.:
33
AF XY:
0.0000135
AC XY:
1
AN XY:
74330
show subpopulations
African (AFR)
AF:
0.0000483
AC:
2
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5206
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10614
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67996
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000129
Hom.:
0
Bravo
AF:
0.00000756
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.00000824
AC:
1
EpiCase
AF:
0.0000545
EpiControl
AF:
0.00

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:7Other:1
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Cystic fibrosis Uncertain:3Other:1
Nov 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 89 of the CFTR protein (p.Tyr89Cys). This variant is present in population databases (rs397508418, gnomAD 0.003%). This missense change has been observed in individual(s) with clinical features of CFTR-related conditions (PMID: 10790225, 17272608, 26098992, 27488443). ClinVar contains an entry for this variant (Variation ID: 53541). 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. -

Feb 14, 2024
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Y89C variant (also known as c.266A>G), located in coding exon 3 of the CFTR gene, results from an A to G substitution at nucleotide position 266. The tyrosine at codon 89 is replaced by cysteine, an amino acid with highly dissimilar properties. This variant was detected as heterozygous in in a male patient with chronic lung infection due to pseudomonas, diffuse bronchiectasis, pancreatic sufficiency, oligospermia, and multiple normal sweat tests; no second alteration was identified (Padoan R et al. Hum Mutat, 2000 May;15:486). Functional studies show that Y89C alteration had a glycosylation pattern and a subcellular distribution comparable to wild-type CFTR, but may still impact channel gating; however, the clinical significance of these findings is unclear (Gen&eacute; GG et al. Hum Mutat, 2008 May;29:738-49). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this alteration remains unclear. -

-
ClinVar Staff, National Center for Biotechnology Information (NCBI)
Significance:not provided
Review Status:no classification provided
Collection Method:literature only

- -

Jul 14, 2023
Johns Hopkins Genomics, Johns Hopkins University
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This CFTR missense variant (rs397508418) is rare (<0.1%) in a large population dataset (gnomADv2.1.1: 2/250722 total alleles; 0.0008%; no homozygotes) and has been reported in ClinVar (Variation ID:53541). It has not been reported in the literature in individuals with features of cystic fibrosis who have a second CF-causing variant, to our knowledge. Two bioinformatic tools queried predict that this substitution would be damaging and a single functional study suggests that this variant may impact CFTR gating. The tyrosine residue at this position is evolutionarily conserved across all species assessed except one. We consider the clinical significance of CFTR c.266A>G to be uncertain at this time. -

not provided Uncertain:2
Feb 27, 2024
ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The CFTR c.266A>G; p.Tyr89Cys variant (rs397508418) is reported in the literature in the heterozygous state without a second CFTR variant identified in individuals affected with cystic fibrosis or CFTR-related disorders (Giusti 2007, Padoan 2000). This variant is also reported in ClinVar (Variation ID: 53541). It 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: 0.905). Functional analyses of the variant protein show normal maturation and trafficking, but some alterations to channel gating (Gene 2008). Due to limited information, the clinical significance of the p.Tyr89Cys variant is uncertain at this time. References: Gene GG et al. N-terminal CFTR missense variants severely affect the behavior of the CFTR chloride channel. Hum Mutat. 2008 May;29(5):738-49. Giusti R et al. New York State cystic fibrosis consortium: the first 2.5 years of experience with cystic fibrosis newborn screening in an ethnically diverse population. Pediatrics. 2007 Feb;119(2):e460-7. Padoan R et al. A novel missense mutation (Y89C) in exon 3 of the CFTR (ABCC7) gene in a young male. Hum Mutat. 2000 May;15(5):486. -

Feb 01, 2023
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

CFTR: PM2, PP3 -

not specified Uncertain:1
Feb 27, 2025
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: CFTR c.266A>G (p.Tyr89Cys) 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 8e-06 in 250722 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.266A>G has been reported in the literature as a non-informative genotype (second allele not specified) among individuals with non-classic features of Cystic Fibrosis and in at-least one newborn with features of Cystic Fibrosis (Giusti_2007, Padoan_2000, Straniero_2016). These data do not allow any conclusion about variant significance. At least one publication reports experimental evidence evaluating an impact on protein function. The most pronounced variant effect results in an activity equivalent to that of wild type protein in an in vitro cellular assay (Bihler_2024). The following publications have been ascertained in the context of this evaluation (PMID: 38388235, 18306312, 17272608, 26098992, 10790225, 27488443). ClinVar contains an entry for this variant (Variation ID: 53541). Based on the evidence outlined above, the variant was classified as uncertain significance. -

CFTR-related disorder Uncertain:1
Jul 02, 2018
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.34
BayesDel_addAF
Pathogenic
0.45
D
BayesDel_noAF
Pathogenic
0.49
CADD
Uncertain
25
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.80
.;D;.;.;T;.
Eigen
Uncertain
0.62
Eigen_PC
Uncertain
0.63
FATHMM_MKL
Uncertain
0.95
D
LIST_S2
Uncertain
0.95
D;D;D;D;D;D
M_CAP
Pathogenic
0.43
D
MetaRNN
Pathogenic
0.90
D;D;D;D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Benign
1.8
.;L;.;.;.;L
PhyloP100
5.5
PrimateAI
Pathogenic
0.80
T
PROVEAN
Pathogenic
-8.3
D;D;.;.;D;.
REVEL
Pathogenic
0.91
Sift
Pathogenic
0.0
D;D;.;.;D;.
Sift4G
Pathogenic
0.0
D;D;.;.;D;.
Polyphen
1.0
.;D;.;.;.;.
Vest4
0.91
MVP
1.0
MPC
0.0043
ClinPred
0.99
D
GERP RS
5.7
Varity_R
0.80
gMVP
0.91
Mutation Taster
=2/98
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.040
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs397508418; hg19: chr7-117149189; API