7-117559465-C-T

Variant names:

• chr7-117559465-C-T
• rs758900656
• NM_000492.4:c.1394C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP2 PP3

The NM_000492.4(CFTR):​c.1394C>T​(p.Thr465Ile) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.000000692 in 1,444,170 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T465N) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CFTR NM_000492.4 missense, splice_region
• Scores: Splicing: ADA: 0.9786
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 5.86
• Publications: 2 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-AS1 (HGNC:40144): (CFTR antisense RNA 1)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 14 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 19 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 chr7-117559465-C-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 495896.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 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: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4	c.1394C>T	p.Thr465Ile	missense_variant, splice_region_variant	Exon 11 of 27	ENST00000003084.11	NP_000483.3
CFTR-AS1	NR_149084.1	n.221+1268G>A		intron_variant	Intron 2 of 2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.1394C>T	p.Thr465Ile	missense_variant, splice_region_variant	Exon 11 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.92e-7 AC: 1 AN: 1444170 Hom.: 0 Cov.: 27 AF XY: 0.00000139 AC XY: 1 AN XY: 719794

African (AFR) AF: 0.00 AC: 0 AN: 32740

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26054

East Asian (EAS) AF: 0.00 AC: 0 AN: 39528

South Asian (SAS) AF: 0.00 AC: 0 AN: 85868

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53230

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5740

European-Non Finnish (NFE) AF: 9.12e-7 AC: 1 AN: 1096550

Other (OTH) AF: 0.00 AC: 0 AN: 59754

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Cystic fibrosis Uncertain:1

Sep 05, 2022

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: curation

This variant was identified in 1 patient with a clinically confirmed diagnosis of cystic fibrosis. The variant was classified in the context of a project re-classifying variants in the German Cystic Fibrosis Registry (Muko.e.V.). Link: https://www.muko.info/angebote/qualitaetsmanagement/register/cf-einrichtungen/mukoweb. Criteria applied: PM2_SUP, PM5, PP3 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D;.;.;D;.
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.89
FATHMM_MKL	Uncertain	0.95	D
LIST_S2	Pathogenic	0.98	D;T;T;D;T
M_CAP	Pathogenic	0.86	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.8	H;.;.;.;.
PhyloP100		5.9
PrimateAI	Uncertain	0.67	T
PROVEAN	Uncertain	-3.2	D;.;.;D;.
REVEL	Pathogenic	0.91
Sift	Uncertain	0.0010	D;.;.;D;.
Sift4G	Pathogenic	0.0010	D;.;.;D;.
Polyphen		1.0	D;.;.;.;.
Vest4		0.86
MutPred		0.93		Gain of stability (P = 0.028);.;.;.;.;
MVP		1.0
MPC		0.012
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.97
gMVP		0.99
Mutation Taster		=24/76	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.98
dbscSNV1_RF	Pathogenic	0.82
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: rs758900656; hg19: chr7-117199519;