5-128335574-A-G

Position:

chr5-128335574-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM1PM2PP2PP3

The NM_001999.4(FBN2):c.3728T>C(p.Ile1243Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,856 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 (★★).

Frequency

Genomes: not found (cov: 32)

Exomes 𝑓: 0.0000027 ( 0 hom. )

Consequence

FBN2
NM_001999.4 missense

Scores

Clinical Significance

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

Conservation

PhyloP100: 7.50

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 links:

FBN2 (HGNC:):

FBN2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PM1

In a domain EGF-like 19; calcium-binding (size 40) in uniprot entity FBN2_HUMAN there are 6 pathogenic changes around while only 1 benign (86%) in NM_001999.4

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), FBN2. . Gene score misZ 1.5491 (greater than the threshold 3.09). Trascript score misZ 3.2752 (greater than threshold 3.09). GenCC has associacion of gene with familial thoracic aortic aneurysm and aortic dissection, carpal tunnel syndrome, macular degeneration, early-onset, congenital contractural arachnodactyly.

PP3

MetaRNN computational evidence supports a deleterious effect, 0.808

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FBN2	NM_001999.4 linkuse as main transcript	c.3728T>C	p.Ile1243Thr	missense_variant	29/65	ENST00000262464.9	NP_001990.2	P35556-1
FBN2	XM_017009228.3 linkuse as main transcript	c.3575T>C	p.Ile1192Thr	missense_variant	28/64		XP_016864717.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FBN2	ENST00000262464.9 linkuse as main transcript	c.3728T>C	p.Ile1243Thr	missense_variant	29/65	1	NM_001999.4	ENSP00000262464.4		P35556-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251306

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135808

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 SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000274

AC:

AN:

1461856

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727232

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000360

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

Cov.:

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

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 27, 2021

The p.I1243T variant (also known as c.3728T>C), located in coding exon 29 of the FBN2 gene, results from a T to C substitution at nucleotide position 3728. The isoleucine at codon 1243 is replaced by threonine, an amino acid with similar properties, and is located in the cbEGF-like #16 domain. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Congenital contractural arachnodactyly

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 03, 2017

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. 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 C25"). This variant has not been reported in the literature in individuals with FBN2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces isoleucine with threonine at codon 1243 of the FBN2 protein (p.Ile1243Thr). The isoleucine residue is highly conserved and there is a moderate physicochemical difference between isoleucine and threonine. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.16

BayesDel_addAF

Pathogenic

0.51

BayesDel_noAF

Pathogenic

0.49

CADD

Uncertain

DANN

Uncertain

0.98

DEOGEN2

Uncertain

0.72

D;.;D;T;T

Eigen

Uncertain

0.42

Eigen_PC

Uncertain

0.44

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.97

D;.;.;D;D

M_CAP

Uncertain

0.26

MetaRNN

Pathogenic

0.81

D;D;D;D;D

MetaSVM

Pathogenic

0.97

MutationAssessor

Uncertain

2.6

M;.;M;.;.

PrimateAI

Uncertain

0.67

PROVEAN

Uncertain

-3.7

D;.;D;D;D

REVEL

Pathogenic

0.82

Sift

Uncertain

0.025

D;.;D;T;T

Sift4G

Uncertain

0.048

.;.;.;D;T

Polyphen

0.98

D;.;D;.;B

Vest4

0.71

MutPred

0.73

Loss of stability (P = 0.0339);.;Loss of stability (P = 0.0339);.;.;

MVP

0.95

MPC

0.31

ClinPred

0.67

GERP RS

5.3

Varity_R

0.29

gMVP

0.90

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over