7-117509143-G-A

Variant summary

Our verdict is Pathogenic. Variant got 22 ACMG points: 22P and 0B. PVS1PM2PP3_StrongPP5_Very_Strong

The NM_000492.4(CFTR):​c.273+1G>A variant causes a splice donor change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000202 in 1,485,476 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (β˜…β˜…β˜…).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000015 ( 0 hom. )

Consequence

CFTR
NM_000492.4 splice_donor

Scores

5
1
1
Splicing: ADA: 1.000
2

Clinical Significance

Pathogenic reviewed by expert panel P:11

Conservation

PhyloP100: 7.71
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 22 ACMG points.

PVS1
Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
PM2
Very rare variant in population databases, with high coverage;
PP3
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
Variant 7-117509143-G-A is Pathogenic according to our data. Variant chr7-117509143-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 53549.Status of the report is reviewed_by_expert_panel, 3 stars. Variant chr7-117509143-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE UniProt
CFTRNM_000492.4 linkuse as main transcriptc.273+1G>A splice_donor_variant ENST00000003084.11

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Appris UniProt
CFTRENST00000003084.11 linkuse as main transcriptc.273+1G>A splice_donor_variant 1 NM_000492.4 P2P13569-1

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152112
Hom.:
0
Cov.:
33
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:
0.00000399
AC:
1
AN:
250546
Hom.:
0
AF XY:
0.00
AC XY:
0
AN XY:
135452
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:
0.00000883
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000150
AC:
2
AN:
1333364
Hom.:
0
Cov.:
21
AF XY:
0.00
AC XY:
0
AN XY:
670800
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
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:
0.00000100
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152112
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74290
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
ExAC
AF:
0.00000824
AC:
1

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:11
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

Cystic fibrosis Pathogenic:5
Pathogenic, criteria provided, single submittercurationCFTR-FranceJan 29, 2018- -
Pathogenic, criteria provided, single submitterclinical testingMyriad Genetics, Inc.Nov 12, 2019NM_000492.3(CFTR):c.273+1G>A(aka 405+1G>A) is classified as pathogenic in the context of cystic fibrosis and is associated with the classic form of disease. Sources cited for classification include the following: PMID 23974870. Classification of NM_000492.3(CFTR):c.273+1G>A(aka 405+1G>A) is based on the following criteria: The variant is located at a canonical splice site, is expected to disrupt gene function and is reported in individuals with the relevant phenotype. Please note: this variant was assessed in the context of healthy population screening.Γ’β‚¬Ε‘Γƒβ€žΓƒΒΆΓ’Λ†Ε‘Γƒβ€˜Γ’Λ†Ε‘Γ‚Β£ -
Pathogenic, reviewed by expert panelresearchCFTR2Mar 17, 2017- -
Pathogenic, criteria provided, single submitterclinical testingAmbry GeneticsMar 03, 2023The c.273+1G>A intronic variant results from a G to A substitution one nucleotide after coding exon 3 of the CFTR gene. Alterations that disrupt the canonical splice site are expected to cause aberrant splicing, resulting in an abnormal protein or a transcript that is subject to nonsense-mediated mRNA decay. Based on data from gnomAD, the A allele has an overall frequency of <0.001% (1/250546) total alleles studied. The highest observed frequency was 0.001% (1/113238) of European (non-Finnish) alleles. This variant, also known as c.405+1G>A in published literature, has been reported in multiple individuals with an elevated sweat chloride level in The Clinical and Functional TRanslation of CFTR (CFTR2) database (available at http://cftr2.org. Accessed 07/25/2022). This nucleotide position is highly conserved in available vertebrate species. Functional in vitro studies found that cells carrying this pathogenic mutation had elevated sweat chloride levels and decreased lung function (Sosnay, 2013). In silico splice site analysis predicts that this alteration will weaken the native splice donor site. Based on the available evidence, this alteration is classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpOct 14, 2023This sequence change affects a donor splice site in intron 3 of the CFTR gene. RNA analysis indicates that disruption of this splice site induces altered splicing and may result in an absent or disrupted protein product. This variant is present in population databases (rs121908791, gnomAD 0.0009%). Disruption of this splice site has been observed in individual(s) with cystic fibrosis (PMID: 7506605, 23974870, 28546993). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. This variant is also known as 405+1G>A. ClinVar contains an entry for this variant (Variation ID: 53549). Studies have shown that disruption of this splice site results in skipping of exon 3 and introduces a premature termination codon (PMID: 7506605). The resulting mRNA is expected to undergo nonsense-mediated decay. For these reasons, this variant has been classified as Pathogenic. -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingQuest Diagnostics Nichols Institute San Juan CapistranoSep 08, 2020The variant is located in a canonical splice-donor site and interferes with normal CFTR mRNA splicing. The variant has been reported in individuals affected with cystic fibrosis in the published literature (PMID: 22975760 (2013), 23974870 (2013), 15948195 (2005), 11336401 (2001), 7506605 (1993)). The variant has been shown to result in a frameshift resulting in premature termination of protein synthesis (PMID: 7506605 (1993)). The frequency of this variant in the general population is consistent with pathogenicity. Therefore, the variant is classified as pathogenic. -
Pathogenic, criteria provided, single submitterclinical testingCenter for Pediatric Genomic Medicine, Children's Mercy Hospital and ClinicsOct 19, 2015- -
not specified Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpOct 12, 2017Variant summary: Variant summary: The CFTR c.273+1G>A variant involves the alteration of a conserved intronic nucleotide. One in silico tool predicts a damaging outcome for this variant. 4/5 splice prediction tools predict significant impact on normal splicing. These predictions were confirmed by a functional study, where authors showed that this change eliminated canonical donor site and lead to exon skipping in epithelial CFTR mRNA, subsequently introducing a frameshift with premature stop codon (Drk_1993). This variant was found in 1/245276 control chromosomes at a frequency of 0.0000041, 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 individuals presented with classical CF (Sosnay_2013). In addition, multiple clinical diagnostic laboratories/reputable databases classified this variant as pathogenic. Taken together, this variant is classified as pathogenic. -
CFTR-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Mar 17, 2017- -
Cystic fibrosis;C0238339:Hereditary pancreatitis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation;C2749757:Bronchiectasis with or without elevated sweat chloride 1 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsMar 19, 2022- -
Bronchiectasis with or without elevated sweat chloride 1 Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingBaylor GeneticsJul 31, 2023- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.63
D
BayesDel_noAF
Pathogenic
0.41
CADD
Pathogenic
33
DANN
Uncertain
1.0
Eigen
Pathogenic
1.2
Eigen_PC
Pathogenic
1.1
FATHMM_MKL
Pathogenic
0.97
D
MutationTaster
Benign
1.0
D;D
GERP RS
5.7

Splicing

Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
1.0
dbscSNV1_RF
Pathogenic
0.93
SpliceAI score (max)
0.86
Details are displayed if max score is > 0.2
DS_DL_spliceai
0.86
Position offset: -1

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: rs121908791; hg19: chr7-117149197; API