NM_000492.4:c.948delT

Variant names:

• chr7-117540175-CT-C
• rs75528968
• NM_000492.4:c.948delT

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1 PP5_Very_Strong

The NM_000492.4(CFTR):​c.948delT​(p.Phe316LeufsTer12) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000349 in 1,461,730 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.000035 (0 hom.)
• Consequence: CFTR NM_000492.4 frameshift
• Clinical Significance: Pathogenic reviewed by expert panel P:17
• Conservation: PhyloP100: 1.90
• Publications: 3 publications found

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: Orphanet, Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Laboratory for Molecular Medicine
• 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)

ACMG classification

Our verdict: Pathogenic. The variant received 16 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PP5: Variant 7-117540175-CT-C is Pathogenic according to our data. Variant chr7-117540175-CT-C is described in ClinVar as Pathogenic. ClinVar VariationId is 7163.Status of the report is reviewed_by_expert_panel, 3 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000492.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	NM_000492.4	MANE Select	c.948delT	p.Phe316LeufsTer12	frameshift	Exon 8 of 27	NP_000483.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	ENST00000003084.11	TSL:1 MANE Select	c.948delT	p.Phe316LeufsTer12	frameshift	Exon 8 of 27	ENSP00000003084.6	P13569-1
	CFTR	ENST00000699602.1		c.948delT	p.Phe316LeufsTer12	frameshift	Exon 8 of 27	ENSP00000514471.1	A0A8V8TNH2
	CFTR	ENST00000889206.1		c.948delT	p.Phe316LeufsTer12	frameshift	Exon 8 of 26	ENSP00000559265.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000239 AC: 6 AN: 251272 AF XY: 0.0000221

Gnomad AFR exome AF: 0.0000615

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000440

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000349 AC: 51 AN: 1461730 Hom.: 0 Cov.: 31 AF XY: 0.0000316 AC XY: 23 AN XY: 727156

African (AFR) AF: 0.0000299 AC: 1 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.0000450 AC: 50 AN: 1111898

Other (OTH) AF: 0.00 AC: 0 AN: 60388

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000189

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
10	-	-	Cystic fibrosis (10)
4	-	-	not provided (4)
1	-	-	Bronchiectasis with or without elevated sweat chloride 1 (1)
1	-	-	CFTR-related disorder (1)
1	-	-	Cystic fibrosis diagnostic test (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		1.9
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.13		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs75528968; hg19: chr7-117180229;