rs201309310

Variant summary

Our verdict is Uncertain significance. The variant received -5 ACMG points: 0P and 5B. BP2BS1

This summary comes from the ClinGen Evidence Repository: The NM_000138 c.59A>G, is a missense variant in FBN1 predicted to cause a substitution of a Tyrosine by a Cysteine at amino acid 20 (p.Tyr20Cys). This variant was found in a proband with aortic root dilatation and a systemic score of 7 or above which is a highly specific phenotype for Marfan syndrome, however, a pathogenic splice variant in FBN1 was also identified in cis in this individual (BP2). The variant segregates with the disease in 4 affected family members, who also carry the pathogenic splice variant in FBN1. The variant in FBN1 has been reported 12 times in ClinVar: 3 times as likely benign, 8 times as uncertain significance and once as likely pathogenic (Variation ID: 161245). This variant has been identified in 37 individuals of European non-Finnish origin (MAF: 0.029%) (BS1; https://gnomad.broadinstitute.org/ version 2.1.1). The constraint z-score for missense variants affecting FBN1 is 5.06, however due to the presence of two benign arguments, PP2 cannot be used. In summary, this variant meets criteria to be classified as likely benign for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP: BS1, BP2 LINK:https://erepo.genome.network/evrepo/ui/classification/CA016208/MONDO:0007947/022

Frequency

Genomes: 𝑓 0.00016 ( 0 hom., cov: 33)
Exomes 𝑓: 0.00026 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

3
15

Clinical Significance

Uncertain significance reviewed by expert panel P:1U:9B:4O:1

Conservation

PhyloP100: 3.86

Publications

10 publications found
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 Gene-Disease associations (from GenCC):
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
  • Marfan syndrome
    Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen, G2P, PanelApp Australia, Orphanet, Ambry Genetics
  • Acromicric dysplasia
    Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
  • progeroid and marfanoid aspect-lipodystrophy syndrome
    Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
  • stiff skin syndrome
    Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Weill-Marchesani syndrome 2, dominant
    Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
  • geleophysic dysplasia
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • isolated ectopia lentis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • neonatal Marfan syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Weill-Marchesani syndrome
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • ectopia lentis 1, isolated, autosomal dominant
    Inheritance: AD Classification: LIMITED Submitted by: G2P
  • Shprintzen-Goldberg syndrome
    Inheritance: AD, Unknown Classification: LIMITED, NO_KNOWN Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received -5 ACMG points.

BP2
For more information check the summary or visit ClinGen Evidence Repository.
BS1
For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN1NM_000138.5 linkc.59A>G p.Tyr20Cys missense_variant Exon 2 of 66 ENST00000316623.10 NP_000129.3 P35555
FBN1NM_001406716.1 linkc.59A>G p.Tyr20Cys missense_variant Exon 1 of 65 NP_001393645.1
FBN1NM_001406717.1 linkc.59A>G p.Tyr20Cys missense_variant Exon 2 of 9 NP_001393646.1
FBN1NM_001406718.1 linkc.59A>G p.Tyr20Cys missense_variant Exon 2 of 3 NP_001393647.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN1ENST00000316623.10 linkc.59A>G p.Tyr20Cys missense_variant Exon 2 of 66 1 NM_000138.5 ENSP00000325527.5 P35555

Frequencies

GnomAD3 genomes
AF:
0.000164
AC:
25
AN:
152152
Hom.:
0
Cov.:
33
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:
0.000207
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000147
AC:
37
AN:
251386
AF XY:
0.000103
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.0000463
Gnomad NFE exome
AF:
0.000299
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000256
AC:
374
AN:
1461816
Hom.:
0
Cov.:
30
AF XY:
0.000231
AC XY:
168
AN XY:
727210
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39696
South Asian (SAS)
AF:
0.0000812
AC:
7
AN:
86258
European-Finnish (FIN)
AF:
0.0000187
AC:
1
AN:
53352
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.000316
AC:
351
AN:
1112010
Other (OTH)
AF:
0.000199
AC:
12
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
22
45
67
90
112
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
20
40
60
80
100
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.000164
AC:
25
AN:
152270
Hom.:
0
Cov.:
33
AF XY:
0.000161
AC XY:
12
AN XY:
74448
show subpopulations
African (AFR)
AF:
0.0000722
AC:
3
AN:
41576
American (AMR)
AF:
0.00
AC:
0
AN:
15306
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5154
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4830
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10620
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.000294
AC:
20
AN:
67998
Other (OTH)
AF:
0.00
AC:
0
AN:
2108
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.519
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000119
Hom.:
0
Bravo
AF:
0.000132
ESP6500AA
AF:
0.00
AC:
0
ESP6500EA
AF:
0.000349
AC:
3
ExAC
AF:
0.000148
AC:
18
EpiCase
AF:
0.000218
EpiControl
AF:
0.000237

ClinVar

Significance: Uncertain significance
Submissions summary: Pathogenic:1Uncertain:9Benign:4Other:1
Revision: reviewed by expert panel
LINK: link

Submissions by phenotype

not provided Uncertain:5Other:1
May 01, 2016
CeGaT Center for Human Genetics Tuebingen
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Diagnostic Laboratory, Department of Genetics, University Medical Center Groningen
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

Nov 19, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Does not affect a cysteine residue within a calcium-binding EGF-like domain of the FBN1 gene; cysteine substitutions in the calcium-binding EGF-like domains represent the majority of pathogenic missense changes associated with FBN1-related disorders (PMID: 12938084); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 25812041, 25637381, 26017485, 16222657, 24941995, 29543232, 12938084) -

Jan 09, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

-
Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

- -

-
GenomeConnect, ClinGen
Significance:not provided
Review Status:no classification provided
Collection Method:phenotyping only

Variant classified as Uncertain significance and reported on 01-28-2021 by GeneDx. GenomeConnect assertions are reported exactly as they appear on the patient-provided report from the testing laboratory. GenomeConnect staff make no attempt to reinterpret the clinical significance of the variant. -

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1Uncertain:1Benign:2
-
Centre for Genomic and Experimental Medicine, University of Edinburgh
Significance:Likely pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Jul 22, 2022
CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Feb 13, 2025
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. -

Jan 06, 2020
Color Diagnostics, LLC DBA Color Health
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Marfan syndrome Uncertain:2
Dec 01, 2022
ClinGen FBN1 Variant Curation Expert Panel, ClinGen
Significance:Uncertain significance
Review Status:reviewed by expert panel
Collection Method:curation

The NM_000138 c.59A>G, is a missense variant in FBN1 predicted to cause a substitution of a Tyrosine by a Cysteine at amino acid 20 (p.Tyr20Cys). This variant was found in a proband with aortic root dilatation and a systemic score of 7 or above which is a highly specific phenotype for Marfan syndrome, however, a pathogenic splice variant in FBN1 was also identified in cis in this individual (BP2). The variant segregates with the disease in 4 affected family members, who also carry the pathogenic splice variant in FBN1. The variant in FBN1 has been reported 12 times in ClinVar: 3 times as likely benign, 8 times as uncertain significance and once as likely pathogenic (Variation ID: 161245). This variant has been identified in 37 individuals of European non-Finnish origin (MAF: 0.029%) (BS1; https://gnomad.broadinstitute.org/ version 2.1.1). The constraint z-score for missense variants affecting FBN1 is 5.06, however due to the presence of two benign arguments, PP2 cannot be used. In summary, this variant meets criteria to be classified as likely benign for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP: BS1, BP2 -

Jun 01, 2014
CSER _CC_NCGL, University of Washington
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:research

- -

not specified Uncertain:1Benign:1
Mar 31, 2016
Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant identified in a genome or exome case(s) and assessed due to predicted null impact of the variant or pathogenic assertions in the literature or databases. Disclaimer: This variant has not undergone full assessment. The following are preliminary notes: Multiple papers report as VUS; ExAC: 16/66648 Europeans; ClinVar: 1 LB, 2 VUS -

Nov 29, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: FBN1 c.59A>G (p.Tyr20Cys) results in a non-conservative amino acid change in 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 0.00015 in 251386 control chromosomes. The observed variant frequency is approximately 1.31 fold of the estimated maximal expected allele frequency for a pathogenic variant in FBN1 causing Marfan Syndrome phenotype (0.00011). This variant has been reported in multiple affected individuals without strong evidence for causality. Although, one paper, Yang_2014 indicates the variant does segregate with disease in the family, however, clinical information is not provided for additional family members. The following publications have been ascertained in the context of this evaluation (PMID: 16222657, 24941995, 26017485). ClinVar contains an entry for this variant (Variation ID: 161245). Based on the evidence outlined above, the variant was classified as likely benign. -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jan 07, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.065
BayesDel_addAF
Benign
-0.049
T
BayesDel_noAF
Uncertain
0.0
CADD
Benign
22
DANN
Benign
0.96
DEOGEN2
Benign
0.38
.;T
Eigen
Benign
-0.34
Eigen_PC
Benign
-0.17
FATHMM_MKL
Benign
0.55
D
LIST_S2
Benign
0.76
T;T
M_CAP
Benign
0.084
D
MetaRNN
Benign
0.38
T;T
MetaSVM
Benign
-0.83
T
PhyloP100
3.9
PrimateAI
Uncertain
0.74
T
PROVEAN
Benign
-0.67
N;D
REVEL
Uncertain
0.37
Sift
Benign
0.17
T;D
Sift4G
Benign
0.19
T;T
Vest4
0.78
MVP
0.97
MPC
0.88
ClinPred
0.094
T
GERP RS
3.5
Mutation Taster
=78/22
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.020
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs201309310; hg19: chr15-48936908; API