rs146469379

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 3P and 4B. PM1PP2BS2

The NM_000138.5(FBN1):c.8027C>T(p.Pro2676Leu) variant causes a missense change. The variant allele was found at a frequency of 0.0000229 in 1,614,104 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P2676S) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.00014 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000011 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 5.61

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 Likely_benign. Variant got -1 ACMG points.

PM1

In a hotspot region, there are 9 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_000138.5

PP2

Missense variant where missense usually causes diseases, FBN1

BS2

High AC in GnomAd at 22 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
FBN1	NM_000138.5 linkuse as main transcript	c.8027C>T	p.Pro2676Leu	missense_variant	64/66	ENST00000316623.10
FBN1	NM_001406716.1 linkuse as main transcript	c.8027C>T	p.Pro2676Leu	missense_variant	63/65

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
FBN1	ENST00000316623.10 linkuse as main transcript	c.8027C>T	p.Pro2676Leu	missense_variant	64/66	1	NM_000138.5	P1

Frequencies

GnomAD3 genomes

AF:

0.000145

AC:

AN:

152214

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000482

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.00

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000360

AC:

AN:

249722

Hom.:

AF XY:

0.0000148

AC XY:

AN XY:

135116

show subpopulations

Gnomad AFR exome

AF:

0.000431

Gnomad AMR exome

AF:

0.0000578

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS 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:

0.0000109

AC:

AN:

1461772

Hom.:

Cov.:

AF XY:

0.00000550

AC XY:

AN XY:

727198

show subpopulations

Gnomad4 AFR exome

AF:

0.000329

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.0000116

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.000138

AC:

AN:

152332

Hom.:

Cov.:

AF XY:

0.000107

AC XY:

AN XY:

74494

show subpopulations

Gnomad4 AFR

AF:

0.000457

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000129

Hom.:

Bravo

AF:

0.000128

ESP6500AA

AF:

0.000227

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.0000494

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 20, 2023	This missense variant replaces proline with leucine at codon 2676 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 reported for this variant. This variant has not been reported in individuals affected with FBN1-related disorders in the literature. This variant has been identified in 11/281132 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. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Aug 30, 2021	The p.P2676L variant (also known as c.8027C>T), located in coding exon 63 of the FBN1 gene, results from a C to T substitution at nucleotide position 8027. The proline at codon 2676 is replaced by leucine, an amino acid with similar properties. This amino acid position is well conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Marfan syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

All of Us Research Program, National Institutes of Health

Dec 18, 2023

Variant of Uncertain Significance due to insufficient evidence: This missense variant is located in the calcium-binding EGF-like motif 47 of the FBN1 protein. Computational prediction tools and conservation analyses are inconclusive regarding the impact of this variant on the protein function. Computational splicing tools suggest that this variant may not impact RNA splicing. To our knowledge, functional assays have not been performed for this variant nor has this variant been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 11/275450 chromosomes in the general population by the Genome Aggregation Database (gnomAD). Available evidence is insufficient to determine the pathogenicity of this variant conclusively. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Jul 26, 2022

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Although located in a calcium-binding EGF-like domain of the FBN1 gene, it does not affect a cysteine residue within this domain; cysteine substitutions in the calcium-binding EGF-like domains represent the majority of pathogenic missense changes associated with FBN1-related disorders (Collod-Beroud et al., 2003) -

Marfan syndrome;C0265287:Acromicric dysplasia;C1858556:MASS syndrome;C1861456:Stiff skin syndrome;C1869115:Weill-Marchesani syndrome 2, dominant;C3280054:Geleophysic dysplasia 2;C3541518:Ectopia lentis 1, isolated, autosomal dominant;C4310796:Progeroid and marfanoid aspect-lipodystrophy syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 25, 2021

- -

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

Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Apr 01, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.11

BayesDel_addAF

Benign

0.0075

BayesDel_noAF

Uncertain

0.10

Cadd

Uncertain

Dann

Uncertain

1.0

Eigen

Uncertain

0.44

Eigen_PC

Uncertain

0.54

FATHMM_MKL

Uncertain

0.94

LIST_S2

Uncertain

0.89

M_CAP

Uncertain

0.086

MetaRNN

Uncertain

0.68

MetaSVM

Uncertain

0.22

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.64

PROVEAN

Pathogenic

-4.9

REVEL

Pathogenic

0.67

Sift

Benign

0.14

Sift4G

Benign

0.19

Vest4

0.73

MVP

0.83

MPC

1.4

ClinPred

0.27

GERP RS

5.8

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