Genetic Variant FBN2:p.Pro2723Arg (chr5-128263449-G-C) – ACMG Classification: Uncertain_significance (2 pts)

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_001999.4(FBN2):c.8168C>G(p.Pro2723Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,386 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P2723L) 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

Scores

Clinical Significance

Not reported in ClinVar

Conservation

PhyloP100: 2.04

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)

FBN2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN2	NM_001999.4 link	c.8168C>G	p.Pro2723Arg	missense_variant	Exon 63 of 65	ENST00000262464.9	NP_001990.2
FBN2	XM_017009228.3 link	c.8015C>G	p.Pro2672Arg	missense_variant	Exon 62 of 64		XP_016864717.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein
FBN2	ENST00000262464.9 link	c.8168C>G	p.Pro2723Arg	missense_variant	Exon 63 of 65	1	NM_001999.4	ENSP00000262464.4
FBN2	ENST00000703782.1 link	n.283C>G		non_coding_transcript_exon_variant	Exon 2 of 2
FBN2	ENST00000703783.1 link	n.*179C>G		downstream_gene_variant

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461386

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727046

show subpopulations

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

33462

American (AMR)

AF:

0.00

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26130

East Asian (EAS)

AF:

0.00

AC:

AN:

39698

South Asian (SAS)

AF:

0.00

AC:

AN:

86232

European-Finnish (FIN)

AF:

0.00

AC:

AN:

53418

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

9.00e-7

AC:

AN:

1111578

Other (OTH)

AF:

0.00

AC:

AN:

60376

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.325

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

Age Distribution

Exome Het

Variant carriers

<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.:

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.17

BayesDel_addAF

Uncertain

0.11

BayesDel_noAF

Uncertain

-0.080

CADD

Benign

(source)

DANN

Benign

0.94

DEOGEN2

Uncertain

0.72

D;.;D

Eigen

Uncertain

0.26

Eigen_PC

Uncertain

0.24

FATHMM_MKL

Benign

0.75

LIST_S2

Benign

0.68

T;.;.

M_CAP

Benign

0.048

MetaRNN

Uncertain

0.64

D;D;D

MetaSVM

Uncertain

0.56

MutationAssessor

Benign

0.83

L;.;L

PhyloP100

2.0

PrimateAI

Uncertain

0.63

PROVEAN

Uncertain

-3.6

D;.;D

REVEL

Uncertain

0.54

Sift

Benign

0.24

T;.;T

Polyphen

0.98

D;.;D

Vest4

0.69

MutPred

0.59

Gain of sheet (P = 0.0266);.;Gain of sheet (P = 0.0266);

MVP

0.59

MPC

0.26

ClinPred

0.85

GERP RS

5.2

Varity_R

0.18

gMVP

0.53

Mutation Taster

=64/36

polymorphism

(source)

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.28

Details are displayed if max score is > 0.2

DS_DG_spliceai

0.28

Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

Age Distribution

ClinVar

Computational scores

Splicing

Publications

Other links and lift over