5-128393177-C-T

Variant summary

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

The NM_001999.4(FBN2):​c.1423G>A​(p.Gly475Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000297 in 1,614,154 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 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. G475R) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00011 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000021 ( 0 hom. )

Consequence

FBN2
NM_001999.4 missense

Scores

4
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:4B:1

Conservation

PhyloP100: 2.35

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=0.11869359).
BS1
Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.000112 (17/152292) while in subpopulation AMR AF = 0.00105 (16/15304). AF 95% confidence interval is 0.000656. There are 0 homozygotes in GnomAd4. There are 9 alleles in the male GnomAd4 subpopulation. Median coverage is 33. This position passed quality control check. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
BS2
High AC in GnomAd4 at 17 AD gene.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN2NM_001999.4 linkc.1423G>A p.Gly475Ser missense_variant Exon 10 of 65 ENST00000262464.9 NP_001990.2
FBN2XM_017009228.3 linkc.1270G>A p.Gly424Ser missense_variant Exon 9 of 64 XP_016864717.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN2ENST00000262464.9 linkc.1423G>A p.Gly475Ser missense_variant Exon 10 of 65 1 NM_001999.4 ENSP00000262464.4
FBN2ENST00000508989.5 linkc.1324G>A p.Gly442Ser missense_variant Exon 9 of 33 2 ENSP00000425596.1
FBN2ENST00000703787.1 linkn.1130G>A non_coding_transcript_exon_variant Exon 9 of 10

Frequencies

GnomAD3 genomes
AF:
0.000112
AC:
17
AN:
152174
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00105
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:
0.0000478
AC:
12
AN:
251098
AF XY:
0.0000590
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.000231
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.000109
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00000882
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000212
AC:
31
AN:
1461862
Hom.:
0
Cov.:
31
AF XY:
0.0000248
AC XY:
18
AN XY:
727234
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33478
American (AMR)
AF:
0.000134
AC:
6
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.0000756
AC:
3
AN:
39700
South Asian (SAS)
AF:
0.0000116
AC:
1
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000189
AC:
21
AN:
1111984
Other (OTH)
AF:
0.00
AC:
0
AN:
60394
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.470
Heterozygous variant carriers
0
2
4
7
9
11
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:
0.000112
AC:
17
AN:
152292
Hom.:
0
Cov.:
33
AF XY:
0.000121
AC XY:
9
AN XY:
74462
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41560
American (AMR)
AF:
0.00105
AC:
16
AN:
15304
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4828
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
294
European-Non Finnish (NFE)
AF:
0.0000147
AC:
1
AN:
68012
Other (OTH)
AF:
0.00
AC:
0
AN:
2112
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.510
Heterozygous variant carriers
0
1
2
3
4
5
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:
0.0000376
Hom.:
0
Bravo
AF:
0.000136
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:4Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

Congenital contractural arachnodactyly Uncertain:1Benign:1
Feb 03, 2025
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Jan 12, 2018
Illumina Laboratory Services, Illumina
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1
Dec 01, 2015
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.G475S variant (also known as c.1423G>A), located in coding exon 10 of the FBN2 gene, results from a G to A substitution at nucleotide position 1423. The glycine at codon 475 is replaced by serine, an amino acid with similar properties. This variant was previously reported in the SNPDatabase as rs200440156. Based on data from the 1000 Genomes Project, the A allele has an overall frequency of approximately 0.05% (1/2098) total alleles studied. The highest observed frequency was 0.86% (1/116) Mexican-American alleles. In population based cohorts in NHLBI Exome Sequencing Project (ESP), this variant was not observed in 6503 samples (13006 alleles) with coverage at this position. This amino acid position is well 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 variant remains unclear. -

not provided Uncertain:1
May 01, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Has not been previously published as pathogenic or benign to our knowledge; In silico analysis indicates that this missense variant does not alter protein structure/function -

Congenital contractural arachnodactyly;C4015286:Macular degeneration, early-onset Uncertain:1
Nov 10, 2021
Fulgent Genetics, Fulgent Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.070
BayesDel_addAF
Benign
-0.14
T
BayesDel_noAF
Benign
-0.17
CADD
Benign
20
DANN
Benign
0.88
DEOGEN2
Benign
0.24
T;.;T;T
Eigen
Benign
-0.52
Eigen_PC
Benign
-0.59
FATHMM_MKL
Benign
0.44
N
LIST_S2
Uncertain
0.88
D;.;.;D
M_CAP
Benign
0.062
D
MetaRNN
Benign
0.12
T;T;T;T
MetaSVM
Benign
-0.63
T
MutationAssessor
Uncertain
2.1
M;.;M;.
PhyloP100
2.3
PrimateAI
Uncertain
0.68
T
PROVEAN
Benign
-1.3
N;.;N;N
REVEL
Uncertain
0.36
Sift
Benign
0.26
T;.;T;T
Sift4G
Benign
0.34
.;.;.;T
Polyphen
0.95
P;.;P;P
Vest4
0.49
MVP
0.65
MPC
0.62
ClinPred
0.048
T
GERP RS
3.2
Varity_R
0.025
gMVP
0.60
Mutation Taster
=83/17
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs200440156; hg19: chr5-127728870; COSMIC: COSV52514024; API