15-48516333-T-C

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 1P and 3B. PP2BP4_ModerateBP6

The NM_000138.5(FBN1):​c.1177A>G​(p.Met393Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000204 in 1,613,728 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/19 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. M393T) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

1
16

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:1

Conservation

PhyloP100: 0.0720

Publications

3 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: Likely_benign. The variant received -2 ACMG points.

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 Marfan syndrome, Weill-Marchesani syndrome 2, dominant, progeroid and marfanoid aspect-lipodystrophy syndrome, geleophysic dysplasia, Shprintzen-Goldberg syndrome, stiff skin syndrome, familial thoracic aortic aneurysm and aortic dissection, isolated ectopia lentis, ectopia lentis 1, isolated, autosomal dominant, Acromicric dysplasia, neonatal Marfan syndrome, Weill-Marchesani syndrome.
BP4
Computational evidence support a benign effect (MetaRNN=0.08129078).
BP6
Variant 15-48516333-T-C is Benign according to our data. Variant chr15-48516333-T-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 527179.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN1NM_000138.5 linkc.1177A>G p.Met393Val missense_variant Exon 11 of 66 ENST00000316623.10 NP_000129.3 P35555
FBN1NM_001406716.1 linkc.1177A>G p.Met393Val missense_variant Exon 10 of 65 NP_001393645.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN1ENST00000316623.10 linkc.1177A>G p.Met393Val missense_variant Exon 11 of 66 1 NM_000138.5 ENSP00000325527.5 P35555
FBN1ENST00000559133.6 linkn.1177A>G non_coding_transcript_exon_variant Exon 11 of 67 1 ENSP00000453958.2 H0YND0
FBN1ENST00000674301.2 linkn.1177A>G non_coding_transcript_exon_variant Exon 11 of 68 ENSP00000501333.2 A0A6I8PL22
FBN1ENST00000537463.6 linkn.636+21378A>G intron_variant Intron 7 of 30 5 ENSP00000440294.2 F6U495

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152134
Hom.:
0
Cov.:
32
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:
0.0000147
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000160
AC:
4
AN:
250308
AF XY:
0.0000148
show subpopulations
Gnomad AFR exome
AF:
0.0000621
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000546
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000177
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461594
Hom.:
0
Cov.:
33
AF XY:
0.0000234
AC XY:
17
AN XY:
727110
show subpopulations
African (AFR)
AF:
0.0000897
AC:
3
AN:
33454
American (AMR)
AF:
0.00
AC:
0
AN:
44720
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39692
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86252
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53370
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5694
European-Non Finnish (NFE)
AF:
0.0000225
AC:
25
AN:
1111908
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60372
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.498
Heterozygous variant carriers
0
2
4
6
8
10
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome 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
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152134
Hom.:
0
Cov.:
32
AF XY:
0.00
AC XY:
0
AN XY:
74324
show subpopulations
African (AFR)
AF:
0.0000241
AC:
1
AN:
41428
American (AMR)
AF:
0.00
AC:
0
AN:
15274
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5198
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4818
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10608
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68020
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
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:
0.00
Hom.:
0
Bravo
AF:
0.0000113

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Marfan syndrome Uncertain:1
Dec 13, 2023
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 methionine with valine at codon 393 of the FBN1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with Mendelian vascular anomalies (PMID: 28655553) and in an individual affected with Marfan syndrome-related disorder (PMID: 31730815). This variant has been identified in 5/281696 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. -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
Dec 23, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces methionine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 393 of the FBN1 protein (p.Met393Val). This variant is present in population databases (no rsID available, gnomAD 0.005%). This missense change has been observed in individuals with clinical features of FBN1-related conditions (PMID: 28655553, 31730815; internal data). ClinVar contains an entry for this variant (Variation ID: 527179). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is not expected to disrupt FBN1 protein function with a negative predictive value of 95%. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Familial thoracic aortic aneurysm and aortic dissection Benign:1
Jul 19, 2024
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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.052
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.47
CADD
Benign
9.4
DANN
Benign
0.57
Eigen
Benign
-0.99
Eigen_PC
Benign
-0.86
FATHMM_MKL
Benign
0.15
N
LIST_S2
Benign
0.49
T
M_CAP
Uncertain
0.16
D
MetaRNN
Benign
0.081
T
MetaSVM
Benign
-0.97
T
PhyloP100
0.072
PrimateAI
Benign
0.28
T
PROVEAN
Benign
-0.71
N
REVEL
Benign
0.19
Sift
Benign
0.55
T
Sift4G
Benign
0.66
T
Vest4
0.11
MutPred
0.34
Loss of disorder (P = 0.1494);
MVP
0.24
MPC
0.53
ClinPred
0.0098
T
GERP RS
-3.1
Mutation Taster
=97/3
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: rs983129867; hg19: chr15-48808530; COSMIC: COSV57330158; API