dbSNP rs878854021: CFTR:c.4243-7delT (chr7-117666898-AT-A) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000492.4(CFTR):c.4243-7delT variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000632 in 1,613,806 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000039 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000066 ( 0 hom. )

Consequence

CFTR
NM_000492.4 splice_region, intron

Scores

Not classified

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1U:4B:1

Conservation

PhyloP100: 0.282

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4 link	c.4243-7delT		splice_region_variant, intron_variant	Intron 26 of 26	ENST00000003084.11	NP_000483.3	P13569-1A0A024R730

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11 link	c.4243-7delT		splice_region_variant, intron_variant	Intron 26 of 26	1	NM_000492.4	ENSP00000003084.6		P13569-1

Frequencies

GnomAD3 genomes

AF:

0.0000394

AC:

AN:

152142

Hom.:

Cov.:

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:

0.0000882

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000200

AC:

AN:

249892

Hom.:

AF XY:

0.0000148

AC XY:

AN XY:

135150

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:

0.0000445

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000657

AC:

AN:

1461546

Hom.:

Cov.:

AF XY:

0.0000688

AC XY:

AN XY:

727080

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.0000756

Gnomad4 OTH exome

AF:

0.000199

GnomAD4 genome

AF:

0.0000394

AC:

AN:

152260

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74436

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:

0.0000882

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000434

Hom.:

Bravo

AF:

0.0000378

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1Uncertain:4Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Dec 12, 2019

Mayo Clinic Laboratories, Mayo Clinic

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Feb 07, 2023

ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The CFTR c.4243-7del variant (rs878854021), to our knowledge, is not reported in the medical literature but is reported in the CFTR- France database in 2 individuals with CBAVD when found in trans with another pathogenic variant (see link). This variant is reported in ClinVar (Variation ID: 237857) and is found in the non-Finnish European population with an allele frequency of 0.005% (5/112352 alleles) in the Genome Aggregation Database. This is an intronic deletion, and computational analyses (Alamut Visual Plus v.1.5.1) predict that this variant may impact splicing by weakening the nearby canonical acceptor splice site. Due to limited information, the clinical significance of this variant is uncertain at this time. References: Link to CFTR France: https://cftr.iurc.montp.inserm.fr/cftr/ -

Cystic fibrosis

Uncertain:1Benign:1

Jun 06, 2023

Johns Hopkins Genomics, Johns Hopkins University

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This CFTR intronic variant (rs878854021) is rare (<0.1%) in a large population dataset (gnomADv3.1.2: 6/152142 total alleles; 0.004%; no homozygotes) and has been reported in ClinVar (Variation ID:237857). It has not been reported in the literature in individuals with cystic fibrosis, to our knowledge. Bioinformatic analysis predicts that this intronic variant may weaken the native acceptor splice site although this has not been confirmed experimentally to our knowledge. We consider the clinical significance of CFTR c.4243-7del to be uncertain at this time. -

Mar 13, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

CFTR-related disorder

Pathogenic:1

Mar 26, 2018

CFTR-France

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

- -

not specified

Uncertain:1

Dec 05, 2016

Quest Diagnostics Nichols Institute San Juan Capistrano

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.40

Details are displayed if max score is > 0.2

DS_AG_spliceai

0.40

Position offset: -15

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over