15-48489983-C-T

Variant names:

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 5P and 5B. PM1PP2PP3_ModerateBP6BS2

The NM_000138.5(FBN1):c.2950G>A(p.Val984Ile) variant causes a missense change. The variant allele was found at a frequency of 0.0000149 in 1,614,006 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). Synonymous variant affecting the same amino acid position (i.e. V984V) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 31)

Exomes 𝑓: 0.000014 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:8B:7

Conservation

PhyloP100: 4.96

Variant links:

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]

FBN1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 0 ACMG points.

PM1

In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 3 benign, 11 uncertain in NM_000138.5

PP2

Missense variant in the FBN1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 1311 curated pathogenic missense variants (we use a threshold of 10). The gene has 112 curated benign missense variants. Gene score misZ: 5.0644 (above the threshold of 3.09). Trascript score misZ: 8.1787 (above the threshold of 3.09). GenCC associations: The gene is linked to MASS syndrome, Weill-Marchesani syndrome, geleophysic dysplasia, Shprintzen-Goldberg syndrome, Acromicric dysplasia, familial thoracic aortic aneurysm and aortic dissection, progeroid and marfanoid aspect-lipodystrophy syndrome, ectopia lentis 1, isolated, autosomal dominant, Marfan syndrome, Weill-Marchesani syndrome 2, dominant, isolated ectopia lentis, neonatal Marfan syndrome, stiff skin syndrome.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.882

BP6

Variant 15-48489983-C-T is Benign according to our data. Variant chr15-48489983-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 457184.We mark this variant Likely_benign, oryginal submissions are: {Uncertain_significance=8, Likely_benign=7}.

BS2

High AC in GnomAdExome4 at 20 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN1	NM_000138.5 link	c.2950G>A	p.Val984Ile	missense_variant	Exon 25 of 66	ENST00000316623.10	NP_000129.3	P35555
FBN1	NM_001406716.1 link	c.2950G>A	p.Val984Ile	missense_variant	Exon 24 of 65		NP_001393645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10 link	c.2950G>A	p.Val984Ile	missense_variant	Exon 25 of 66	1	NM_000138.5	ENSP00000325527.5		P35555

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152114

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000441

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000199

AC:

AN:

251474

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.000109

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000137

AC:

AN:

1461892

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000162

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152114

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74318

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000441

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000113

ExAC

AF:

0.0000494

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:8Benign:7

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection

Uncertain:3

May 13, 2024

Color Diagnostics, LLC DBA Color Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces valine with isoleucine at codon 984 of the FBN1 protein. Computational prediction tools indicate that this variant's impact on protein structure and function is inconclusive. To our knowledge, functional studies have not been performed for this variant. This variant has been reported in one individual affected with classic Marfan syndrome with cardiovascular manifestations (PMID: 10694921) and in one individual affected with hypertrophic cardiomyopathy (PMID: 23590259). This variant has also been reported in one family, with one individual affected with thoracic aortic aneurysm and dissection; this variant did not segregate with disease and was identified in three unaffected family members (PMID: 27146836). This variant has been identified in 6/282854 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Dec 16, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.V984I variant (also known as c.2950G>A), located in coding exon 24 of the FBN1 gene, results from a G to A substitution at nucleotide position 2950. The valine at codon 984 is replaced by isoleucine, an amino acid with highly similar properties. This variant was reported in individual(s) with features consistent with thoracic aortic aneurysm and dissection (Grau U et al. Hum Mutat, 1998;12:137; Poninska JK et al. J Transl Med, 2016 May;14:115). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the available evidence, the clinical significance of this variant remains unclear. -

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases did not allow this variant to be ruled in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not provided

Uncertain:2Benign:1

Aug 01, 2020

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 24, 2024

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In silico analysis indicates that this missense variant does not alter protein structure/function; Does not affect a cysteine or calcium-binding residue within an EGF-like domain or a TGF-binding protein domain of the FBN1 gene; cysteine substitutions in the EGF-like domains represent the majority of pathogenic missense changes associated with FBN1-related disorders (PMID: 12938084); This variant is associated with the following publications: (PMID: 10694921, 12203992, 23590259, 12938084, 27146836) -

Mar 10, 2022

Revvity Omics, Revvity

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Marfan syndrome

Uncertain:2

Jul 29, 2024

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces valine with isoleucine at codon 984 of the FBN1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been performed for this variant. This variant has been reported in an individual affected with classic Marfan syndrome with cardiovascular manifestations (PMID: 10694921), in an individual affected with thoracic aortic aneurysms and dissections associated with Marfan syndrome (PMID: 27146836), and in an individual affected with hypertrophic cardiomyopathy (PMID: 23590259). This variant was also reported in one case non-obstructive HCM (PMID: 23590259). This variant has been identified in 6/282854 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. However, the evidence from the literature, in combination with allele frequency data from public databases where available, was not sufficient to rule this variant in or out of causing disease. Therefore, this variant is classified as a variant of unknown significance. -

not specified

Uncertain:1

Nov 25, 2024

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

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: FBN1 c.2950G>A (p.Val984Ile) results in a conservative amino acid change located in the TGF-beta binding (TB) domain (IPR017878) 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 2e-05 in 251474 control chromosomes. The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.2950G>A has been reported in the literature in individuals affected with Marfan Syndrome or hypertrophic cardiomyopathy (e.g. Grau_1998, Fokstuen_2014, Poninska_2016, Collod-Beroud_1997). These data do not allow any conclusion about variant significance. 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: 9016526, 23590259, 10694921, 27146836). ClinVar contains an entry for this variant (Variation ID: 457184). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Stiff skin syndrome

Benign:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Weill-Marchesani syndrome

Benign:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Geleophysic dysplasia

Benign:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Acromicric dysplasia

Benign:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection

Benign:1

Jun 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Ectopia lentis 1, isolated, autosomal dominant

Benign:1

Apr 27, 2017

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.082

BayesDel_addAF

Uncertain

0.14

BayesDel_noAF

Pathogenic

0.14

CADD

Uncertain

DANN

Uncertain

1.0

Eigen

Uncertain

0.28

Eigen_PC

Uncertain

0.27

FATHMM_MKL

Uncertain

0.97

LIST_S2

Uncertain

0.86

M_CAP

Uncertain

0.14

MetaRNN

Pathogenic

0.88

MetaSVM

Uncertain

0.46

PrimateAI

Uncertain

0.58

PROVEAN

Benign

-0.40

REVEL

Uncertain

0.54

Sift

Benign

0.32

Sift4G

Benign

0.27

Vest4

0.73

MutPred

0.85

Gain of disorder (P = 0.1568);

MVP

0.87

MPC

0.44

ClinPred

0.27

GERP RS

5.7

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

Publications

LitVar

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

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over