rs397508535

Variant names:

• chr7-117611740-A-C
• rs397508535
• NM_000492.4:c.3299A>C

Your query was ambiguous. Multiple possible variants found:

• chr7-117611740-A-C
• chr7-117611740-A-G

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1 PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000492.4(CFTR):​c.3299A>C​(p.Gln1100Pro) variant causes a missense change. The variant allele was found at a frequency of 0.00000137 in 1,461,462 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 Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CFTR NM_000492.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9 O:1
• Conservation: PhyloP100: 6.55
• Publications: 16 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 17 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 12 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, 0.984
• PP5: Variant 7-117611740-A-C is Pathogenic according to our data. Variant chr7-117611740-A-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 53711.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.3299A>C	p.Gln1100Pro	missense_variant	Exon 20 of 27	ENST00000003084.11	NP_000483.3
CFTR-AS2	NR_199597.1	n.177+4489T>G		intron_variant	Intron 2 of 2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CFTR	ENST00000003084.11	c.3299A>C	p.Gln1100Pro	missense_variant	Exon 20 of 27	1	NM_000492.4	ENSP00000003084.6

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251108 AF XY: 0.00000737

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000290

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: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461462 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727020

African (AFR) AF: 0.00 AC: 0 AN: 33456

American (AMR) AF: 0.0000448 AC: 2 AN: 44658

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39686

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53392

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111760

Other (OTH) AF: 0.00 AC: 0 AN: 60372

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Cystic fibrosis Pathogenic:6 Other:1

Sep 13, 2023

Johns Hopkins Genomics, Johns Hopkins University

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

CFTR c.3299A>C has been identified in multiple individuals with elevated sweat chloride concentration and features of cystic fibrosis (CF) who also have a second CF-causing CFTR variant, although the phase of these variants has not been confirmed. This CFTR variant (rs397508535) is rare (<0.1%) in a large population dataset (gnomADv2.1.1: 1/251108 total alleles; 0.0004%; no homozygotes) and has been reported in ClinVar (Variation ID: 53711). A single peer-reviewed functional study indicates that this variant may impact CFTR trafficking. The glutamine residue at this position is evolutionarily conserved across most species assessed, but not fish. We consider CFTR c.3299A>C to be likely pathogenic. -

Jan 05, 2017

Counsyl

Significance: Likely pathogenic

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. -

-

ClinVar Staff, National Center for Biotechnology Information (NCBI)

Significance: not provided

Review Status: no classification provided

Collection Method: literature only

- -

Jun 13, 2024

Ambry Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.Q1100P pathogenic mutation (also known as c.3299A>C), located in coding exon 20 of the CFTR gene, results from an A to C substitution at nucleotide position 3299. The glutamine at codon 1100 is replaced by proline, an amino acid with similar properties. This variant has been identified in the homozygous state and in conjunction with other CFTR variant(s) in individuals with features consistent with cystic fibrosis (Guardiano M et al. Rev Port Pneumol, 2005;11:381-406; Essawi O et al. Dis. Markers, 2015;2015:458653; Mota LR et al. Mol Biol Rep, 2018 Dec;45:2045-2051; Ambry internal data). In multiple assays testing CFTR function, this variant showed functionally abnormal results (Ramalho SS et al. Int J Mol Sci, 2021 Dec;23:; 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. This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). Based on the supporting evidence, this variant is interpreted as a disease-causing mutation. -

Dec 14, 2023

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

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: CFTR c.3299A>C (p.Gln1100Pro) results in a non-conservative amino acid change located in the ABC transporter type 1, transmembrane domain of the encoded protein sequence. Four of four in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4e-06 in 251108 control chromosomes. c.3299A>C has been reported in the literature in multiple individuals affected with Cystic Fibrosis (Mota_2018, Siryani_2015, Alonso_2007, Chillon_1994). These data indicate that the variant is very likely to be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. Five submitters have cited clinical-significance assessments for this variant to ClinVar after 2014: four submitters have classified the variant as likely pathogenic/pathogenic while one classified as VUS. Based on the evidence outlined above, the variant was classified as pathogenic. -

Nov 05, 2018

Mendelics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 25, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamine, which is neutral and polar, with proline, which is neutral and non-polar, at codon 1100 of the CFTR protein (p.Gln1100Pro). This variant is present in population databases (rs397508535, gnomAD 0.003%). This missense change has been observed in individual(s) with cystic fibrosis (PMID: 16240056, 26208274, 27145507, 30232781). ClinVar contains an entry for this variant (Variation ID: 53711). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CFTR protein function with a positive predictive value of 80%. This variant disrupts the p.Gln1100 amino acid residue in CFTR. Other variant(s) that disrupt this residue have been observed in individuals with CFTR-related conditions (PMID: 23240968), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

CFTR-related disorder Pathogenic:1

Nov 11, 2020

Natera, Inc.

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Cystic fibrosis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation Pathogenic:1

-

Baylor Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Bronchiectasis with or without elevated sweat chloride 1 Pathogenic:1

Mar 13, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.32
CADD	Uncertain	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.57	D;.;.;T;.
Eigen	Pathogenic	0.69
Eigen_PC	Pathogenic	0.70
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Uncertain	0.96	D;D;D;D;D
M_CAP	Pathogenic	0.59	D
MetaRNN	Pathogenic	0.98	D;D;D;D;D
MetaSVM	Uncertain	0.61	D
MutationAssessor	Benign	2.0	M;.;.;.;.
PhyloP100		6.6
PrimateAI	Uncertain	0.58	T
PROVEAN	Benign	-0.83	N;.;.;N;.
REVEL	Pathogenic	0.73
Sift	Benign	0.19	T;.;.;T;.
Sift4G	Uncertain	0.055	T;.;.;T;.
Polyphen		0.99	D;.;.;.;.
Vest4		0.93
MutPred		0.94		Loss of MoRF binding (P = 0.0692);.;.;.;.;
MVP		1.0
MPC		0.011
ClinPred		0.87	D
GERP RS		5.7
PromoterAI		0.0032	Neutral
Varity_R		0.94
gMVP		0.97
Mutation Taster		=3/97	disease causing (ClinVar)

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: rs397508535; hg19: chr7-117251794;