7-117540156-C-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP3PP5

The NM_000492.4(CFTR):ā€‹c.926C>Gā€‹(p.Ala309Gly) variant causes a missense change. The variant allele was found at a frequency of 0.0000205 in 1,613,322 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).

Frequency

Genomes: š‘“ 0.000039 ( 0 hom., cov: 32)
Exomes š‘“: 0.000018 ( 0 hom. )

Consequence

CFTR
NM_000492.4 missense

Scores

5
7
7

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2U:6O:1

Conservation

PhyloP100: 5.72
Variant links:
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1
In a domain ABC transmembrane type-1 1 (size 284) in uniprot entity CFTR_HUMAN there are 65 pathogenic changes around while only 10 benign (87%) in NM_000492.4
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.786
PP5
Variant 7-117540156-C-G is Pathogenic according to our data. Variant chr7-117540156-C-G is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 54086.We mark this variant Likely_pathogenic, oryginal submissions are: {Likely_pathogenic=1, not_provided=1, Uncertain_significance=5, Pathogenic=1}.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
CFTRNM_000492.4 linkuse as main transcriptc.926C>G p.Ala309Gly missense_variant 8/27 ENST00000003084.11 NP_000483.3

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
CFTRENST00000003084.11 linkuse as main transcriptc.926C>G p.Ala309Gly missense_variant 8/271 NM_000492.4 ENSP00000003084 P2P13569-1

Frequencies

GnomAD3 genomes
AF:
0.0000395
AC:
6
AN:
152088
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.000328
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD3 exomes
AF:
0.0000478
AC:
12
AN:
251076
Hom.:
0
AF XY:
0.0000737
AC XY:
10
AN XY:
135716
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000289
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad SAS exome
AF:
0.000196
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000185
AC:
27
AN:
1461234
Hom.:
0
Cov.:
30
AF XY:
0.0000289
AC XY:
21
AN XY:
726948
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.0000224
Gnomad4 ASJ exome
AF:
0.00
Gnomad4 EAS exome
AF:
0.0000756
Gnomad4 SAS exome
AF:
0.000162
Gnomad4 FIN exome
AF:
0.0000375
Gnomad4 NFE exome
AF:
0.00000540
Gnomad4 OTH exome
AF:
0.0000166
GnomAD4 genome
AF:
0.0000395
AC:
6
AN:
152088
Hom.:
0
Cov.:
32
AF XY:
0.0000539
AC XY:
4
AN XY:
74278
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.000328
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000147
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000453
ExAC
AF:
0.0000412
AC:
5

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Pathogenic:2Uncertain:6Other:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Cystic fibrosis Pathogenic:2Uncertain:3Other:1
Uncertain significance, criteria provided, single submitterclinical testingCounsylDec 28, 2017- -
Uncertain significance, criteria provided, single submitterclinical testingGenome-Nilou LabSep 05, 2021- -
not provided, no classification providedliterature onlyClinVar Staff, National Center for Biotechnology Information (NCBI)-- -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 15, 2024This sequence change replaces alanine, which is neutral and non-polar, with glycine, which is neutral and non-polar, at codon 309 of the CFTR protein (p.Ala309Gly). This variant is present in population databases (rs397508818, gnomAD 0.02%). This missense change has been observed in individual(s) with clinical features of CFTR-related conditions (PMID: 26856987, 30811104). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 54086). 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%. For these reasons, this variant has been classified as Pathogenic. -
Likely pathogenic, criteria provided, single submitterclinical testingNeuberg Centre For Genomic Medicine, NCGMFeb 14, 2023The missense c.926C>G (p.Ala309Gly) variant in CFTR gene has been reported in compound heterozygous state in multiple individuals affected with cystic fibrosis (Ramalho AS, 2016; Salvatore D et al. 2016; Nectoux J, et al. 2006). The p.Ala309Gly variant has allele frequency 0.005% in gnomAD Exomes and is novel (not in any individuals) in 1000 Genomes. This variant has been reported to the ClinVar database as Pathogenic / Uncertain Significance. The amino acid change p.Ala309Gly in CFTR is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. The amino acid Ala at position 309 is changed to a Gly changing protein sequence and it might alter its composition and physico-chemical properties. Functional studies are required to prove the pathogenicity for the variant, for these reasons, this variant has been classified as Likely Pathogenic. -
Uncertain significance, criteria provided, single submitterclinical testingAmbry GeneticsDec 12, 2023The p.A309G variant (also known as c.926C>G), located in coding exon 8 of the CFTR gene, results from a C to G substitution at nucleotide position 926. The alanine at codon 309 is replaced by glycine, an amino acid with similar properties. This alteration was identified in trans with p.F508del in an individual with elevated sweat chloride levels and pancreatic sufficiency (Salvatore D et al. Clin Genet, 2016 Aug;90:186-7). This amino acid position is well 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. -
not specified Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpAug 13, 2024Variant summary: CFTR c.926C>G (p.Ala309Gly) results in a non-conservative amino acid change located in the ABC transporter type 1, transmembrane domain (IPR011527) of the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 4.8e-05 in 251076 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in CFTR causing Cystic Fibrosis, allowing no conclusion about variant significance. c.926C>G has been reported in the literature in two individuals affected with Cystic Fibrosis with elevated sweat chloride levels, one of whom carries F508del in trans (Cartault_1998, Salvatore_2016). It has also been reported in individuals with CAVD (e.g. Yuan_2019, Wang_2020, Gaikwad_2020, Li_2022) and in an individual undergoing CFTR genetic testing with a suspicion of CF or a CFTR-RD (Nykamp_2021). These data indicate that the variant may be associated with disease. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publications have been ascertained in the context of this evaluation (PMID: 16596947, 9842999, 11504857, 34145097, 34931337, 32777524, 17020473, 34196078, 25735457, 26856987, 32020786, 30811104). ClinVar contains an entry for this variant (Variation ID: 54086). Based on the evidence outlined above, the variant was classified as VUS-possibly pathogenic. -
not provided Uncertain:1
Uncertain significance, criteria provided, single submitterclinical testingEurofins Ntd Llc (ga)Nov 14, 2017- -
CFTR-related disorder Uncertain:1
Uncertain significance, no assertion criteria providedclinical testingNatera, Inc.Apr 14, 2021- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.24
BayesDel_addAF
Pathogenic
0.16
D
BayesDel_noAF
Pathogenic
0.27
CADD
Uncertain
23
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.70
D;.;.;D;.
Eigen
Benign
0.12
Eigen_PC
Uncertain
0.29
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Uncertain
0.86
D;D;D;D;D
M_CAP
Pathogenic
0.47
D
MetaRNN
Pathogenic
0.79
D;D;D;D;D
MetaSVM
Uncertain
0.080
D
MutationAssessor
Benign
1.6
L;.;.;.;L
MutationTaster
Benign
1.0
D;D
PrimateAI
Benign
0.47
T
PROVEAN
Benign
-2.0
N;.;.;N;.
REVEL
Uncertain
0.59
Sift
Benign
0.059
T;.;.;D;.
Sift4G
Uncertain
0.051
T;.;.;T;.
Polyphen
0.0030
B;.;.;.;.
Vest4
0.66
MutPred
0.88
Gain of glycosylation at S308 (P = 0.0411);Gain of glycosylation at S308 (P = 0.0411);Gain of glycosylation at S308 (P = 0.0411);.;Gain of glycosylation at S308 (P = 0.0411);
MVP
0.99
MPC
0.0040
ClinPred
0.078
T
GERP RS
5.4
Varity_R
0.84
gMVP
0.87

Splicing

Name
Calibrated prediction
Score
Prediction
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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs397508818; hg19: chr7-117180210; API