rs778966916
Variant summary
Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PM2PP3PP5_Very_Strong
The NM_000138.5(FBN1):c.4583-5A>G variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★★).
Frequency
Genomes: not found (cov: 32)
Consequence
FBN1
NM_000138.5 splice_region, splice_polypyrimidine_tract, intron
NM_000138.5 splice_region, splice_polypyrimidine_tract, intron
Scores
2
Splicing: ADA: 0.9996
2
Clinical Significance
Conservation
PhyloP100: 1.46
Genes affected
FBN1 (HGNC:3603): (fibrillin 1) This gene encodes a member of the fibrillin family of proteins. The encoded preproprotein is proteolytically processed to generate two proteins including the extracellular matrix component fibrillin-1 and the protein hormone asprosin. Fibrillin-1 is an extracellular matrix glycoprotein that serves as a structural component of calcium-binding microfibrils. These microfibrils provide force-bearing structural support in elastic and nonelastic connective tissue throughout the body. Asprosin, secreted by white adipose tissue, has been shown to regulate glucose homeostasis. Mutations in this gene are associated with Marfan syndrome and the related MASS phenotype, as well as ectopia lentis syndrome, Weill-Marchesani syndrome, Shprintzen-Goldberg syndrome and neonatal progeroid syndrome. [provided by RefSeq, Apr 2016]
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ACMG classification
Classification made for transcript
Verdict is Pathogenic. Variant got 11 ACMG points.
PM2
?
Very rare variant in population databases, with high coverage;
PP3
?
Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
PP5
?
Variant 15-48468107-T-C is Pathogenic according to our data. Variant chr15-48468107-T-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 406332.Status of the report is reviewed_by_expert_panel, 3 stars.
Transcripts
RefSeq
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | MANE | UniProt |
---|---|---|---|---|---|---|---|
FBN1 | NM_000138.5 | c.4583-5A>G | splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant | ENST00000316623.10 | |||
FBN1 | NM_001406716.1 | c.4583-5A>G | splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant |
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | #exon/exons | TSL | MANE | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|
FBN1 | ENST00000316623.10 | c.4583-5A>G | splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant | 1 | NM_000138.5 | P1 |
Frequencies
GnomAD3 genomes ? Cov.: 32
GnomAD3 genomes
?
Cov.:
32
GnomAD4 exome Cov.: 32
GnomAD4 exome
Cov.:
32
GnomAD4 genome ? Cov.: 32
GnomAD4 genome
?
Cov.:
32
ClinVar
Significance: Likely pathogenic
Submissions summary: Pathogenic:2
Revision: reviewed by expert panel
LINK: link
Submissions by phenotype
Marfan syndrome Pathogenic:1
Likely pathogenic, reviewed by expert panel | curation | ClinGen FBN1 Variant Curation Expert Panel, ClinGen | Jun 15, 2023 | The NM_000138.5 c.4583-5A>G variant in FBN1 is a variant in the splice acceptor region of intron 37. Computational splice prediction algorithms predict that this variant impacts splicing (PP3). This variant was identified in the literature and public databases in two individuals with clinical diagnoses of Marfan syndrome including once as de novo in an individual with phenotype consistent with but not highly specific to FBN1 and in an individual with aortic aneurysm and other features suggestive of Marfan syndrome; it was also found to segregate with disease in at least one affected family member (PS4_moderate, PM6_supporting; PMID: 25101912, Invitae internal data, ClinVar ID: 406332). It was also identified in a third individual with a clinical diagnosis of Marfan syndrome (PP4; Johns Hopkins). This variant is not present in gnomAD v2.1.1 or v3.1.2 (PM2_supporting; https://gnomad.broadinstitute.org/). In summary, this variant meets criteria to be classified as likely pathogenic for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP (PS4_moderate, PM2_supporting, PM6_supporting, PP3, PP4). - |
Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1
Likely pathogenic, criteria provided, single submitter | clinical testing | Invitae | Nov 15, 2018 | This sequence change falls in intron 37 of the FBN1 mRNA. It does not directly change the encoded amino acid sequence of the FBN1 protein. This variant is not present in population databases (ExAC no frequency). In summary this is a rare intronic variant that is predicted to affect protein splicing and has been reported as de novo in an affected individual. For these reasons, this variant has ben classified as Likely Pathogenic. Algorithms developed to predict the effect of nucleotide changes on mRNA splicing suggest that this intronic variant may alter mRNA splicing, but this prediction has not been confirmed by published transcriptional studies. This sequence change was reported as de novo in an individual affected with Marfan syndrome (PMID: 25101912, 25652356). - |
Computational scores
Source:
Name
Calibrated prediction
Score
Prediction
BayesDel_noAF
Benign
Cadd
Uncertain
Dann
Benign
Splicing
Name
Calibrated prediction
Score
Prediction
dbscSNV1_ADA
Pathogenic
dbscSNV1_RF
Pathogenic
SpliceAI score (max)
Details are displayed if max score is > 0.2
DS_AG_spliceai
Position offset: -1
Find out detailed SpliceAI scores and Pangolin per-transcript scores at