chr7-117665565-G-T
Variant summary
Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong
The NM_000492.4(CFTR):c.4242+1G>T variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000126 in 1,589,424 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★★).
Frequency
Consequence
NM_000492.4 splice_donor, intron
Scores
Clinical Significance
Conservation
Publications
- cystic fibrosisInheritance: 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 deferensInheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
- hereditary chronic pancreatitisInheritance: AD Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)
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ACMG classification
Our verdict: Pathogenic. The variant received 18 ACMG points.
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.4242+1G>T | splice_donor intron | N/A | NP_000483.3 |
Ensembl Transcripts
| Selected | Gene | Transcript | Tags | HGVSc | HGVSp | Effect | Exon Rank | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|---|
| CFTR | ENST00000003084.11 | TSL:1 MANE Select | c.4242+1G>T | splice_donor intron | N/A | ENSP00000003084.6 | |||
| CFTR | ENST00000699606.1 | n.2411G>T | non_coding_transcript_exon | Exon 3 of 3 | |||||
| CFTR | ENST00000699602.1 | c.4236+1G>T | splice_donor intron | N/A | ENSP00000514471.1 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152208Hom.: 0 Cov.: 33 show subpopulations
GnomAD2 exomes AF: 0.00000399 AC: 1AN: 250642 AF XY: 0.00 show subpopulations
GnomAD4 exome AF: 6.96e-7 AC: 1AN: 1437216Hom.: 0 Cov.: 26 AF XY: 0.00 AC XY: 0AN XY: 716478 show subpopulations ⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152208Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0AN XY: 74352 show subpopulations
ClinVar
Submissions by phenotype
Cystic fibrosis Pathogenic:6
This sequence change affects a donor splice site in intron 26 of the CFTR gene. While this variant is not anticipated to result in nonsense mediated decay, it likely alters RNA splicing and results in a disrupted protein product. This variant is present in population databases (rs372227120, gnomAD 0.0009%). Disruption of this splice site has been observed in individual(s) with cystic fibrosis (PMID: 1379210, 7682196, 15074370). This variant is also known as 4374+1G>T. ClinVar contains an entry for this variant (Variation ID: 53930). Variants that disrupt the consensus splice site are a relatively common cause of aberrant splicing (PMID: 17576681, 9536098). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic.
The c.4242+1G>T intronic pathogenic mutation (also known as 4374+1G>T) results from a G to T substitution one nucleotide after coding exon 26 of the CFTR gene. This alteration was reported in one patient with cystic fibrosis who had pancreatic insufficiency, elevated sweat chloride levels, and decreased lung function (Dork et al. Genomics. 1993 Mar;15(3):688-91). This individual also had the deltaF508 mutation, however phase was unknown. In addition to the clinical data presented in the literature, since alterations that disrupt the canonical splice donor site are typically deleterious in nature, this alteration is interpreted as a disease-causing mutation (ACMG Recommendations for Standards for Interpretation and Reporting of Sequence Variations. Revision 2007. Genet Med. 2008;10:294).
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.
This variant was identified in 2 unrelated patients 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: PVS1_STR, PS1_SUP, PM2_SUP, PM3_VSTR, PP4
CFTR-related disorder Pathogenic:1
Cystic fibrosis;C0403814:Congenital bilateral aplasia of vas deferens from CFTR mutation Pathogenic:1
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at