rs1375786834

Variant names:

• chr7-117590370-C-A
• rs1375786834
• NM_000492.4:c.1697C>A

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PP2 PP3_Strong PP5

The NM_000492.4(CFTR):​c.1697C>A​(p.Ala566Asp) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,450,892 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 Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. A566T) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 U:2
• Conservation: PhyloP100: 7.31
• Publications: 6 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)

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 22 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 17 uncertain in NM_000492.4
• PM2: Very rare variant in population databases, with high coverage
• 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, 0.986
• PP5: Variant 7-117590370-C-A is Pathogenic according to our data. Variant chr7-117590370-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 556179.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CFTR	NM_000492.4	c.1697C>A	p.Ala566Asp	missense_variant	Exon 13 of 27	ENST00000003084.11	NP_000483.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.1697C>A	p.Ala566Asp	missense_variant	Exon 13 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000399 AC: 1 AN: 250370 AF XY: 0.00

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000164

GnomAD4 exome AF: 6.89e-7 AC: 1 AN: 1450892 Hom.: 0 Cov.: 30 AF XY: 0.00 AC XY: 0 AN XY: 721650

African (AFR) AF: 0.00 AC: 0 AN: 33244

American (AMR) AF: 0.00 AC: 0 AN: 44394

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25622

East Asian (EAS) AF: 0.00 AC: 0 AN: 39372

South Asian (SAS) AF: 0.00 AC: 0 AN: 86084

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52586

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5692

European-Non Finnish (NFE) AF: 9.06e-7 AC: 1 AN: 1104242

Other (OTH) AF: 0.00 AC: 0 AN: 59656

GnomAD4 genome Cov.: 32

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Cystic fibrosis Uncertain:2

Jan 17, 2018

Counsyl

Significance: Uncertain significance

Review Status: no assertion criteria provided

Collection Method: clinical testing

This submission and the accompanying classification are no longer maintained by the submitter. For more information on current observations and classification, please contact variantquestions@myriad.com. -

Jul 29, 2022

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.A566D variant (also known as c.1697C>A), located in coding exon 13 of the CFTR gene, results from a C to A substitution at nucleotide position 1697. The alanine at codon 566 is replaced by aspartic acid, an amino acid with dissimilar properties. This alteration has been identified in individuals diagnosed with cystic fibrosis (Alibakhshi R et al. J Cyst Fibros, 2008 Mar;7:102-9; Banjar HH et al. Ann Saudi Med Mar;40:15-24). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Bronchiectasis with or without elevated sweat chloride 1 Pathogenic:1

Mar 02, 2023

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;.;D;.
Eigen	Pathogenic	0.84
Eigen_PC	Pathogenic	0.77
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.93	D;D;D;D
M_CAP	Pathogenic	0.79	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.9	M;.;.;.
PhyloP100		7.3
PrimateAI	Pathogenic	0.79	T
PROVEAN	Pathogenic	-4.7	D;.;D;.
REVEL	Pathogenic	0.94
Sift	Uncertain	0.0030	D;.;D;.
Sift4G	Pathogenic	0.0010	D;.;D;.
Polyphen		1.0	D;.;.;.
Vest4		0.97
MutPred		0.92		Gain of phosphorylation at Y569 (P = 0.0847);.;.;.;
MVP		1.0
MPC		0.013
ClinPred		1.0	D
GERP RS		4.8
Varity_R		0.97
gMVP		0.99
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
Splicevardb		0.0
SpliceAI score (max)		0.010		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: rs1375786834; hg19: chr7-117230424;