rs1218249269

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2BP4_Moderate

The NM_001999.4(FBN2):​c.3220A>G​(p.Ile1074Val) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,496 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/22 in silico tools predict a benign outcome for this variant. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. I1074I) has been classified as Likely benign.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

FBN2
NM_001999.4 missense, splice_region

Scores

3
16

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 0.993

Publications

1 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 0 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
BP4
Computational evidence support a benign effect (MetaRNN=0.2510964).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.3220A>G p.Ile1074Val missense_variant, splice_region_variant Exon 25 of 65 ENST00000262464.9 NP_001990.2 P35556-1
FBN2XM_017009228.3 linkc.3067A>G p.Ile1023Val missense_variant, splice_region_variant Exon 24 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.3220A>G p.Ile1074Val missense_variant, splice_region_variant Exon 25 of 65 1 NM_001999.4 ENSP00000262464.4 P35556-1
FBN2ENST00000508989.5 linkc.3121A>G p.Ile1041Val missense_variant, splice_region_variant Exon 24 of 33 2 ENSP00000425596.1 D6RJI3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.00000398
AC:
1
AN:
251356
AF XY:
0.00
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:
0.00
Gnomad NFE exome
AF:
0.00000879
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
6.84e-7
AC:
1
AN:
1461496
Hom.:
0
Cov.:
31
AF XY:
0.00
AC XY:
0
AN XY:
727076
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33472
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26126
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53342
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
8.99e-7
AC:
1
AN:
1111752
Other (OTH)
AF:
0.00
AC:
0
AN:
60376
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.425
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
Cov.:
32

ClinVar

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

Submissions by phenotype

Congenital contractural arachnodactyly Uncertain:1
May 31, 2017
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

In summary, this variant has uncertain impact on FBN2 function. The available evidence is currently insufficient to determine its role in disease. Therefore, it has been classified as a Variant of Uncertain Significance. This sequence change replaces isoleucine with valine at codon 1074 of the FBN2 protein (p.Ile1074Val). The isoleucine residue is moderately conserved and there is a small physicochemical difference between isoleucine and valine. This variant is not present in population databases (ExAC no frequency). This variant 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 do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.099
BayesDel_addAF
Benign
-0.047
T
BayesDel_noAF
Benign
-0.31
CADD
Benign
18
DANN
Benign
0.72
DEOGEN2
Benign
0.27
T;.;T;T
Eigen
Benign
-0.44
Eigen_PC
Benign
-0.30
FATHMM_MKL
Uncertain
0.93
D
LIST_S2
Benign
0.71
T;.;.;T
M_CAP
Benign
0.048
D
MetaRNN
Benign
0.25
T;T;T;T
MetaSVM
Uncertain
-0.24
T
MutationAssessor
Benign
0.30
N;.;N;.
PhyloP100
0.99
PrimateAI
Benign
0.45
T
PROVEAN
Benign
-0.47
N;.;N;N
REVEL
Uncertain
0.38
Sift
Benign
0.34
T;.;T;T
Sift4G
Benign
0.44
.;.;.;T
Polyphen
0.0040
B;.;B;B
Vest4
0.23
MutPred
0.46
Gain of ubiquitination at K1078 (P = 0.1084);.;Gain of ubiquitination at K1078 (P = 0.1084);.;
MVP
0.48
MPC
0.20
ClinPred
0.090
T
GERP RS
4.3
Varity_R
0.057
gMVP
0.59
Mutation Taster
=75/25
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: rs1218249269; hg19: chr5-127680200; API