chr5-128311423-T-C

Variant summary

Our verdict is Benign. The variant received -7 ACMG points: 0P and 7B. BP4_ModerateBS1_SupportingBS2

The NM_001999.4(FBN2):​c.4951A>G​(p.Ile1651Val) variant causes a missense, splice region change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000013 in 1,461,782 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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 (★).

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

FBN2
NM_001999.4 missense, splice_region

Scores

1
7
10

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 8.02

Publications

3 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: Benign. The variant received -7 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.22741255).
BS1
Variant frequency is greater than expected in population amr. GnomAdExome4 allele frequency = 0.000013 (19/1461782) while in subpopulation AMR AF = 0.00038 (17/44722). AF 95% confidence interval is 0.000242. There are 0 homozygotes in GnomAdExome4. There are 3 alleles in the male GnomAdExome4 subpopulation. Median coverage is 31. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAdExome4 at 19 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.4951A>G p.Ile1651Val missense_variant, splice_region_variant Exon 39 of 65 ENST00000262464.9 NP_001990.2 P35556-1
FBN2XM_017009228.3 linkc.4798A>G p.Ile1600Val missense_variant, splice_region_variant Exon 38 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.4951A>G p.Ile1651Val missense_variant, splice_region_variant Exon 39 of 65 1 NM_001999.4 ENSP00000262464.4 P35556-1
FBN2ENST00000703783.1 linkn.1735A>G splice_region_variant, non_coding_transcript_exon_variant Exon 14 of 38
FBN2ENST00000703785.1 linkn.1654A>G splice_region_variant, non_coding_transcript_exon_variant Exon 13 of 27

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000557
AC:
14
AN:
251284
AF XY:
0.0000221
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000318
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000489
GnomAD4 exome
AF:
0.0000130
AC:
19
AN:
1461782
Hom.:
0
Cov.:
31
AF XY:
0.00000413
AC XY:
3
AN XY:
727194
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33476
American (AMR)
AF:
0.000380
AC:
17
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39688
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53404
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111948
Other (OTH)
AF:
0.0000331
AC:
2
AN:
60390
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.493
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

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
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000113
ExAC
AF:
0.000115
AC:
14

ClinVar

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

Submissions by phenotype

Congenital contractural arachnodactyly Uncertain:1
May 22, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces isoleucine, which is neutral and non-polar, with valine, which is neutral and non-polar, at codon 1651 of the FBN2 protein (p.Ile1651Val). This variant is present in population databases (rs765442038, gnomAD 0.03%). This missense change has been observed in individual(s) with congenital contractural arachnodactyly (Invitae). ClinVar contains an entry for this variant (Variation ID: 573716). An algorithm developed to predict the effect of missense changes on protein structure and function (PolyPhen-2) suggests that this variant is likely to be disruptive. 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
Benign
0.29
BayesDel_addAF
Benign
-0.10
T
BayesDel_noAF
Benign
-0.090
CADD
Uncertain
23
DANN
Uncertain
1.0
DEOGEN2
Benign
0.37
T;.;T
Eigen
Uncertain
0.47
Eigen_PC
Uncertain
0.53
FATHMM_MKL
Pathogenic
1.0
D
LIST_S2
Uncertain
0.94
D;.;.
M_CAP
Benign
0.066
D
MetaRNN
Benign
0.23
T;T;T
MetaSVM
Uncertain
0.48
D
MutationAssessor
Benign
0.29
N;.;N
PhyloP100
8.0
PrimateAI
Uncertain
0.74
T
PROVEAN
Benign
-0.80
N;.;N
REVEL
Uncertain
0.54
Sift
Benign
0.12
T;.;T
Polyphen
0.82
P;.;P
Vest4
0.42
MutPred
0.50
Loss of disorder (P = 0.2604);.;Loss of disorder (P = 0.2604);
MVP
0.52
MPC
0.49
ClinPred
0.23
T
GERP RS
5.1
Varity_R
0.078
gMVP
0.82
Mutation Taster
=61/39
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: rs765442038; hg19: chr5-127647115; API