5-128311415-T-G

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM2PP3_Moderate

The NM_001999.4(FBN2):​c.4959A>C​(p.Glu1653Asp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,810 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E1653K) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

FBN2
NM_001999.4 missense

Scores

10
7
1

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

Conservation

PhyloP100: 0.535

Publications

0 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: Uncertain_significance. The variant received 4 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.883

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.4959A>C p.Glu1653Asp missense_variant Exon 39 of 65 ENST00000262464.9 NP_001990.2
FBN2XM_017009228.3 linkc.4806A>C p.Glu1602Asp missense_variant Exon 38 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.4959A>C p.Glu1653Asp missense_variant Exon 39 of 65 1 NM_001999.4 ENSP00000262464.4
FBN2ENST00000703783.1 linkn.1743A>C non_coding_transcript_exon_variant Exon 14 of 38
FBN2ENST00000703785.1 linkn.1662A>C non_coding_transcript_exon_variant Exon 13 of 27

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461810
Hom.:
0
Cov.:
31
AF XY:
0.00000138
AC XY:
1
AN XY:
727216
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26134
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39690
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00000270
AC:
3
AN:
1111964
Other (OTH)
AF:
0.00
AC:
0
AN:
60392
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.492
Heterozygous variant carriers
0
1
1
2
2
3
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
Cov.:
32

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:2
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
Jul 15, 2019
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.E1653D variant (also known as c.4959A>C), located in coding exon 39 of the FBN2 gene, results from an A to C substitution at nucleotide position 4959. The glutamic acid at codon 1653 is replaced by aspartic acid, an amino acid with highly similar properties. This amino acid position is highly 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. -

Congenital contractural arachnodactyly Uncertain:1
Jun 01, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces glutamic acid with aspartic acid at codon 1653 of the FBN2 protein (p.Glu1653Asp). The glutamic acid residue is highly conserved and there is a small physicochemical difference between glutamic acid and aspartic acid. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with FBN2-related conditions. ClinVar contains an entry for this variant (Variation ID: 528421). 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 and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.23
D
BayesDel_noAF
Uncertain
0.090
CADD
Benign
22
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.80
D;.;D
Eigen
Uncertain
0.39
Eigen_PC
Uncertain
0.24
FATHMM_MKL
Uncertain
0.90
D
LIST_S2
Pathogenic
0.98
D;.;.
M_CAP
Pathogenic
0.32
D
MetaRNN
Pathogenic
0.88
D;D;D
MetaSVM
Pathogenic
1.1
D
MutationAssessor
Pathogenic
3.1
M;.;M
PhyloP100
0.54
PrimateAI
Pathogenic
0.81
D
PROVEAN
Uncertain
-2.6
D;.;D
REVEL
Pathogenic
0.85
Sift
Uncertain
0.0050
D;.;D
Polyphen
0.99
D;.;D
Vest4
0.57
MutPred
0.82
Loss of disorder (P = 0.2533);.;Loss of disorder (P = 0.2533);
MVP
0.92
MPC
0.50
ClinPred
0.98
D
GERP RS
0.22
Varity_R
0.38
gMVP
0.96
Mutation Taster
=79/21
polymorphism

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: rs1554120359; hg19: chr5-127647107; API