rs886038940

Variant summary

Our verdict is Pathogenic. Variant got 17 ACMG points: 17P and 0B. PS1PM1PM2PM5PP2PP3_StrongPP5_Moderate

The NM_000138.5(FBN1):​c.4331G>C​(p.Cys1444Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 11/18 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Likely pathogenic in Lovd. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. C1444Y) has been classified as Likely pathogenic.

Frequency

Genomes: not found (cov: 32)

Consequence

FBN1
NM_000138.5 missense

Scores

14
2
1

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 7.91
Variant links:
Genes affected
FBN1 (HGNC:3603): (fibrillin 1) This gene encodes a member of the fibrillin family of proteins. The encoded preproprotein is proteolytically processed to generate two proteins including the extracellular matrix component fibrillin-1 and the protein hormone asprosin. Fibrillin-1 is an extracellular matrix glycoprotein that serves as a structural component of calcium-binding microfibrils. These microfibrils provide force-bearing structural support in elastic and nonelastic connective tissue throughout the body. Asprosin, secreted by white adipose tissue, has been shown to regulate glucose homeostasis. Mutations in this gene are associated with Marfan syndrome and the related MASS phenotype, as well as ectopia lentis syndrome, Weill-Marchesani syndrome, Shprintzen-Goldberg syndrome and neonatal progeroid syndrome. [provided by RefSeq, Apr 2016]

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ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 17 ACMG points.

PS1
Transcript NM_000138.5 (FBN1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
PM1
In a domain EGF-like 24; calcium-binding (size 41) in uniprot entity FBN1_HUMAN there are 14 pathogenic changes around while only 4 benign (78%) in NM_000138.5
PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr15-48472556-C-T is described in Lovd as [Likely_pathogenic].
PP2
Missense variant in the FBN1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 1311 curated pathogenic missense variants (we use a threshold of 10). The gene has 112 curated benign missense variants. Gene score misZ: 5.0644 (above the threshold of 3.09). Trascript score misZ: 8.1787 (above the threshold of 3.09). GenCC associations: The gene is linked to MASS syndrome, Weill-Marchesani syndrome, geleophysic dysplasia, Shprintzen-Goldberg syndrome, Acromicric dysplasia, familial thoracic aortic aneurysm and aortic dissection, progeroid and marfanoid aspect-lipodystrophy syndrome, ectopia lentis 1, isolated, autosomal dominant, Marfan syndrome, Weill-Marchesani syndrome 2, dominant, isolated ectopia lentis, neonatal Marfan syndrome, stiff skin syndrome.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.994
PP5
Variant 15-48472556-C-G is Pathogenic according to our data. Variant chr15-48472556-C-G is described in ClinVar as [Pathogenic]. Clinvar id is 1453863.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FBN1NM_000138.5 linkc.4331G>C p.Cys1444Ser missense_variant Exon 35 of 66 ENST00000316623.10 NP_000129.3 P35555
FBN1NM_001406716.1 linkc.4331G>C p.Cys1444Ser missense_variant Exon 34 of 65 NP_001393645.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FBN1ENST00000316623.10 linkc.4331G>C p.Cys1444Ser missense_variant Exon 35 of 66 1 NM_000138.5 ENSP00000325527.5 P35555

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD4 exome
Cov.:
36
GnomAD4 genome
Cov.:
32

ClinVar

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

Submissions by phenotype

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1
Jun 19, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance: Pathogenic
Review Status: criteria provided, single submitter
Collection Method: clinical testing

This sequence change replaces cysteine, which is neutral and slightly polar, with serine, which is neutral and polar, at codon 1444 of the FBN1 protein (p.Cys1444Ser). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with clinical features of FBN1-related conditions (Invitae). ClinVar contains an entry for this variant (Variation ID: 1453863). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt FBN1 protein function with a positive predictive value of 95%. This variant affects a cysteine residue in the EGF-like, TGFBP or hybrid motif domains of FBN1. Cysteine residues are believed to be involved in intramolecular disulfide bridges and have been shown to be important for FBN1 protein structure (PMID: 16905551, 19349279). In addition, missense substitutions affecting cysteine residues within these domains are significantly overrepresented among patients with Marfan syndrome (PMID: 16571647, 17701892). This variant disrupts the p.Cys1444 amino acid residue in FBN1. Other variant(s) that disrupt this residue have been observed in individuals with FBN1-related conditions (PMID: 31098894; Invitae), which suggests that this may be a clinically significant amino acid residue. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
1.0
BayesDel_addAF
Pathogenic
0.58
D
BayesDel_noAF
Pathogenic
0.60
CADD
Pathogenic
31
DANN
Uncertain
1.0
Eigen
Pathogenic
1.1
Eigen_PC
Pathogenic
0.98
FATHMM_MKL
Pathogenic
0.99
D
LIST_S2
Pathogenic
0.98
D
M_CAP
Pathogenic
0.96
D
MetaRNN
Pathogenic
0.99
D
MetaSVM
Pathogenic
0.93
D
PrimateAI
Pathogenic
0.82
D
PROVEAN
Pathogenic
-8.8
D
REVEL
Pathogenic
0.95
Sift
Pathogenic
0.0
D
Sift4G
Uncertain
0.0030
D
Vest4
0.99
MutPred
0.91
Gain of disorder (P = 0.0068);
MVP
0.99
MPC
1.6
ClinPred
1.0
D
GERP RS
5.8

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr15-48764753; API