chr15-48430723-C-T

Variant names:

Variant summary

Our verdict is Likely benign. Variant got -1 ACMG points: 5P and 6B. PM1PM5PP2BP4BP6BS2

The NM_000138.5(FBN1):c.6819G>A(p.Met2273Ile) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000613 in 1,613,798 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/18 in silico tools predict a benign outcome for this variant. 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. M2273T) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000065 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:3

Conservation

PhyloP100: 0.860

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 disulfide_bond (size 16) in uniprot entity FBN1_HUMAN there are 11 pathogenic changes around while only 0 benign (100%) in NM_000138.5

PM5

Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.

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.

BP4

Computational evidence support a benign effect (MetaRNN=0.28444052).

BP6

Variant 15-48430723-C-T is Benign according to our data. Variant chr15-48430723-C-T is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 450683.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Benign=1, Uncertain_significance=4}.

BS2

High AC in GnomAdExome4 at 95 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN1	NM_000138.5 link	c.6819G>A	p.Met2273Ile	missense_variant	Exon 56 of 66	ENST00000316623.10	NP_000129.3	P35555
FBN1	NM_001406716.1 link	c.6819G>A	p.Met2273Ile	missense_variant	Exon 55 of 65		NP_001393645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10 link	c.6819G>A	p.Met2273Ile	missense_variant	Exon 56 of 66	1	NM_000138.5	ENSP00000325527.5		P35555

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152190

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000724

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000279

AC:

AN:

251276

Hom.:

AF XY:

0.0000221

AC XY:

AN XY:

135798

show subpopulations

Gnomad AFR exome

AF:

0.0000615

Gnomad AMR exome

AF:

0.0000868

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:

0.0000264

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000650

AC:

AN:

1461608

Hom.:

Cov.:

AF XY:

0.0000729

AC XY:

AN XY:

727120

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.0000671

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000818

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152190

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74344

show subpopulations

Gnomad4 AFR

AF:

0.0000724

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:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000965

Hom.:

Bravo

AF:

0.0000604

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.000119

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:4Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:2

Mar 01, 2021

CeGaT Center for Human Genetics Tuebingen

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 29, 2025

GeneDx

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Has not been previously published as pathogenic or benign to our knowledge; 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: 12938084) -

Familial thoracic aortic aneurysm and aortic dissection

Benign:2

Dec 07, 2021

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Nov 18, 2018

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Marfan syndrome

Uncertain:1

Jun 01, 2018

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified

Uncertain:1

Mar 27, 2023

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.6819G>A (p.Met2273Ile) results in a conservative amino acid change located in the EGF-like domain (IPR000742) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 2.8e-05 in 251276 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. To our knowledge, no occurrence of c.6819G>A in individuals affected with Marfan Syndrome and no experimental evidence demonstrating its impact on protein function have been reported. Six clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as VUS (n=3) and benign/likely benign (n=3). Based on the evidence outlined above, the variant was classified as uncertain significance. -

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

Benign:1

Dec 03, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.24

BayesDel_addAF

Benign

-0.12

BayesDel_noAF

Benign

-0.22

CADD

Benign

DANN

Uncertain

0.98

Eigen

Benign

-0.42

Eigen_PC

Benign

-0.25

FATHMM_MKL

Uncertain

0.90

LIST_S2

Benign

0.71

M_CAP

Benign

0.030

MetaRNN

Benign

0.28

MetaSVM

Benign

-0.50

PrimateAI

Benign

0.36

PROVEAN

Benign

-2.3

REVEL

Benign

0.27

Sift

Benign

0.20

Sift4G

Benign

0.21

Vest4

0.18

MutPred

0.55

Loss of phosphorylation at Y2272 (P = 0.1444);

MVP

0.40

MPC

0.56

ClinPred

0.086

GERP RS

2.0

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.

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