rs878854476

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_001999.4(FBN2):​c.6002G>A​(p.Cys2001Tyr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,174 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 13/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)

Consequence

FBN2
NM_001999.4 missense

Scores

16
1
1

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.91

Publications

2 publications found
Variant links:
Genes affected
FBN2 (HGNC:3604): (fibrillin 2) The protein encoded by this gene is a component of connective tissue microfibrils and may be involved in elastic fiber assembly. Mutations in this gene cause congenital contractural arachnodactyly. [provided by RefSeq, Jul 2008]
FBN2 Gene-Disease associations (from GenCC):
  • congenital contractural arachnodactyly
    Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Orphanet, Labcorp Genetics (formerly Invitae), G2P, Genomics England PanelApp
  • carpal tunnel syndrome
    Inheritance: AD Classification: LIMITED Submitted by: Franklin by Genoox
  • familial thoracic aortic aneurysm and aortic dissection
    Inheritance: AD Classification: LIMITED Submitted by: ClinGen
  • macular degeneration, early-onset
    Inheritance: AD Classification: LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.997

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.6002G>A p.Cys2001Tyr missense_variant Exon 47 of 65 ENST00000262464.9 NP_001990.2 P35556-1
FBN2XM_017009228.3 linkc.5849G>A p.Cys1950Tyr missense_variant Exon 46 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.6002G>A p.Cys2001Tyr missense_variant Exon 47 of 65 1 NM_001999.4 ENSP00000262464.4 P35556-1
FBN2ENST00000703783.1 linkn.2786G>A non_coding_transcript_exon_variant Exon 22 of 38
FBN2ENST00000703785.1 linkn.2705G>A non_coding_transcript_exon_variant Exon 21 of 27

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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
GnomAD4 exome
Cov.:
31
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152174
Hom.:
0
Cov.:
33
AF XY:
0.0000134
AC XY:
1
AN XY:
74352
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5190
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10612
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2090
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:
0.0000712
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Congenital contractural arachnodactyly Uncertain:1
Mar 10, 2016
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces cysteine with tyrosine at codon 2001 of the FBN2 protein (p.Cys2001Tyr). The cysteine residue is highly conserved and there is a large physicochemical difference between cysteine and tyrosine. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a FBN2-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies. In summary, this variant is a novel missense change affecting a residue crucial for protein stability and function. However, segregation and functional evidence implicating this variant are not available. Therefore, it has been classified as a Variant of Uncertain Significance. This variant affects a cysteine residue located within an epidermal growth factor (EGF)–like domain of the FBN2 protein. Cysteine residues in these domains are involved in the formation of disulfide bridges critical for protein structure and stability (PMID: 3495735, 4750422, 16677079). In addition, missense substitutions within the FBN2 EGF-like domains affecting cysteine residues are overrepresented in patients with congenital contractural arachnodactyly (PMID: 18767143). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.59
D
BayesDel_noAF
Pathogenic
0.61
CADD
Pathogenic
27
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.96
D;.;D
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.95
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
1.0
D;.;.
M_CAP
Pathogenic
0.85
D
MetaRNN
Pathogenic
1.0
D;D;D
MetaSVM
Pathogenic
0.94
D
MutationAssessor
Pathogenic
4.8
H;.;H
PhyloP100
7.9
PrimateAI
Pathogenic
0.90
D
PROVEAN
Pathogenic
-9.9
D;.;D
REVEL
Pathogenic
0.97
Sift
Pathogenic
0.0
D;.;D
Polyphen
1.0
D;.;D
Vest4
0.99
MutPred
1.0
Loss of disorder (P = 0.1185);.;Loss of disorder (P = 0.1185);
MVP
0.99
MPC
1.1
ClinPred
1.0
D
GERP RS
5.5
Varity_R
0.94
gMVP
0.99
Mutation Taster
=6/94
disease causing

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

Other links and lift over

dbSNP: rs878854476; hg19: chr5-127637118; API