chr7-117642528-G-T

Variant names:

• chr7-117642528-G-T
• rs11971167
• NM_000492.4:c.3808G>T

Variant summary

Our verdict is Pathogenic. The variant received 11 ACMG points: 11P and 0B. PM1 PM2 PM5 PP2 PP3_Strong

The NM_000492.4(CFTR):​c.3808G>T​(p.Asp1270Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,362 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 drug response (★★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. D1270N) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: drug response reviewed by expert panel U:1 O:1
• Conservation: PhyloP100: 9.43
• Publications: 100 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: 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)

ENSG00000083622 (HGNC:40145):

ACMG classification

Our verdict: Pathogenic. The variant received 11 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 18 uncertain in NM_000492.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr7-117642529-A-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1706020.Status of the report is criteria_provided_single_submitter, 1 stars.
• 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, 0.982

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	NM_000492.4	MANE Select	c.3808G>T	p.Asp1270Tyr	missense	Exon 23 of 27	NP_000483.3
	CFTR-AS2	NR_199597.1		n.65+4823C>A		intron	N/A

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CFTR	ENST00000003084.11	TSL:1 MANE Select	c.3808G>T	p.Asp1270Tyr	missense	Exon 23 of 27	ENSP00000003084.6
	CFTR	ENST00000699602.1		c.3802G>T	p.Asp1268Tyr	missense	Exon 23 of 27	ENSP00000514471.1
	CFTR	ENST00000426809.5	TSL:5	c.3718G>T	p.Asp1240Tyr	missense	Exon 22 of 26	ENSP00000389119.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461362 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 726956

African (AFR) AF: 0.00 AC: 0 AN: 33458

American (AMR) AF: 0.00 AC: 0 AN: 44674

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.00 AC: 0 AN: 39626

South Asian (SAS) AF: 0.00 AC: 0 AN: 86246

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53396

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 9.00e-7 AC: 1 AN: 1111716

Other (OTH) AF: 0.0000166 AC: 1 AN: 60370

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 3

Bravo AF: 0.00000378

ClinVar

Significance: drug response

Submissions summary: Uncertain:1 Other:1

Revision: reviewed by expert panel

Submissions by phenotype

Cystic fibrosis Uncertain:1

Aug 21, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.D1270Y variant (also known as c.3808G>T), located in coding exon 23 of the CFTR gene, results from a G to T substitution at nucleotide position 3808. The aspartic acid at codon 1270 is replaced by tyrosine, an amino acid with highly dissimilar properties. This alteration was identified in an individual diagnosed with cystic fibrosis however a second CFTR alteration was not documented (Raraigh KS et al. J Cyst Fibros, 2022 May;21:463-470). In an assay testing CFTR function, this variant showed a functionally abnormal result (Bihler H et al. J Cyst Fibros, 2024 Feb;:). 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 variant remains unclear.

ivacaftor response - Efficacy Other:1

Mar 24, 2021

PharmGKB

Significance: drug response

Review Status: reviewed by expert panel

Collection Method: curation

PharmGKB Level of Evidence 1A: Level 1A clinical annotations describe variant-drug combinations that have variant-specific prescribing guidance available in a current clinical guideline annotation or an FDA-approved drug label annotation. Annotations of drug labels or clinical guidelines must give prescribing guidance for specific variants (e.g. CYP2C9*3, HLA-B*57:01) or provide mapping from defined allele functions to diplotypes and phenotypes to be used as supporting evidence for a level 1A clinical annotation. Level 1A clinical annotations must also be supported by at least one publication in addition to a clinical guideline or drug label with variant-specific prescribing guidance. Drug-variant association: Efficacy

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.91
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D
Eigen	Pathogenic	0.99
Eigen_PC	Pathogenic	0.92
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.9	M
PhyloP100		9.4
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-7.7	D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.88		Gain of catalytic residue at I1269 (P = 0.0714)
MVP		0.99
MPC		0.015
ClinPred		1.0	D
GERP RS		5.2
Varity_R		0.98
gMVP		0.96
Mutation Taster		=8/92	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs11971167; hg19: chr7-117282582; COSMIC: COSV50116636;