7-117534315-AT-ATT

Variant names:

• chr7-117534315-A-AT
• rs121908771
• NM_000492.4:c.531dupT

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000492.4(CFTR):​c.531dupT​(p.Gly178TrpfsTer5) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: CFTR NM_000492.4 frameshift
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 3.58

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]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 7-117534315-A-AT is Pathogenic according to our data. Variant chr7-117534315-A-AT is described in ClinVar as [Likely_pathogenic]. Clinvar id is 495952.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4	c.531dupT	p.Gly178TrpfsTer5	frameshift_variant	Exon 5 of 27	ENST00000003084.11	NP_000483.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.531dupT	p.Gly178TrpfsTer5	frameshift_variant	Exon 5 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 26

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cystic fibrosis Pathogenic:2

Jul 03, 2017

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: The CFTR c.531dupT (p.Gly178Trpfs) variant results in a premature termination codon, predicted to cause a truncated or absent CFTR protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory (e.g. p.Leu671X, p.Arg709X, p.Glu831X etc.). This variant is absent in 119504 control chromosomes from ExAC. This variant has been reported in one neonate with CF in the compound heterozygous state with p.Phe508del (Simakova_2016; early publication; link: http://www.biorxiv.org/content/biorxiv/early/2016/04/26/050419.full.pdf). The variant has also been reported in a Maldovan CF patient (Scuica_Revista de tiine ale Sntii din Moldova_2015). Taken together, this variant is classified as likely pathogenic. -

Jan 29, 2018

CFTR-France

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: curation

- -

CFTR-related disorder Pathogenic:1

Jun 02, 2021

Natera, Inc.

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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

Other links and lift over

dbSNP: rs121908771; hg19: chr7-117174369;