15-48421982-C-A

Variant names:

• chr15-48421982-C-A
• NM_000138.5:c.7540G>T

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PP4 PP1 PM2_Supporting

This summary comes from the ClinGen Evidence Repository: The NM_000138 c.7540G>T variant is a nonsense variant in FBN1 that is expected to introduce a premature stop codon at this position, likely resulting in an absent or disrupted protein product (PVS1). This variant was found in a proband with a clinical diagnosis of Marfan syndrome and segregates with disease in three affected family members (PP4, PP1; Bichat), as well as in an individual with features suggestive of or consistent with Marfan syndrome (PMID:17627385). This variant is not present in gnomAD v2.1.1 or v3.1.2 (PM2_supporting; https://gnomad.broadinstitute.org/). In summary, this variant meets criteria to be classified as pathogenic for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP: PVS1, PM2_supporting, PP1, PP4. LINK:https://erepo.genome.network/evrepo/ui/classification/CA392325892/MONDO:0007947/022

• Frequency: Genomes: not found (cov: 33)
• Consequence: FBN1 NM_000138.5 stop_gained
• Clinical Significance: Pathogenic reviewed by expert panel P:1
• Conservation: PhyloP100: 7.91

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 ACMG points.

• PVS1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PP1: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN1	NM_000138.5	c.7540G>T	p.Gly2514*	stop_gained	Exon 61 of 66	ENST00000316623.10	NP_000129.3
FBN1	NM_001406716.1	c.7540G>T	p.Gly2514*	stop_gained	Exon 60 of 65		NP_001393645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10	c.7540G>T	p.Gly2514*	stop_gained	Exon 61 of 66	1	NM_000138.5	ENSP00000325527.5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: reviewed by expert panel

Submissions by phenotype

Marfan syndrome Pathogenic:1

Jun 15, 2023

ClinGen FBN1 Variant Curation Expert Panel, ClinGen

Significance: Pathogenic

Review Status: reviewed by expert panel

Collection Method: curation

The NM_000138 c.7540G>T variant is a nonsense variant in FBN1 that is expected to introduce a premature stop codon at this position, likely resulting in an absent or disrupted protein product (PVS1). This variant was found in a proband with a clinical diagnosis of Marfan syndrome and segregates with disease in three affected family members (PP4, PP1; Bichat), as well as in an individual with features suggestive of or consistent with Marfan syndrome (PMID: 17627385). This variant is not present in gnomAD v2.1.1 or v3.1.2 (PM2_supporting; https://gnomad.broadinstitute.org/). In summary, this variant meets criteria to be classified as pathogenic for Marfan syndrome based on the ACMG/AMP criteria applied, as specified by the ClinGen FBN1 VCEP: PVS1, PM2_supporting, PP1, PP4. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	46
DANN	Uncertain	0.99
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	0.99	D
Vest4		0.94
GERP RS		5.9

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: chr15-48714179;