15-48537660-G-C

Position:

chr15-48537660-G-C

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 3P and 6B. PM1PP2BP4_ModerateBS2

The NM_000138.5(FBN1):c.687C>G(p.His229Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000434 in 1,614,106 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. H229H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000034 ( 0 hom. )

Consequence

FBN1
NM_000138.5 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 1.54

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]

FBN1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -3 ACMG points.

PM1

In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000138.5

PP2

Missense variant where missense usually causes diseases, FBN1

BP4

Computational evidence support a benign effect (MetaRNN=0.26033288).

BS2

High AC in GnomAdExome4 at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE
FBN1	NM_000138.5 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant	7/66	ENST00000316623.10
FBN1	NM_001406716.1 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant	6/65
FBN1	NM_001406717.1 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant	7/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris
FBN1	ENST00000316623.10 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant	7/66	1	NM_000138.5	P1
FBN1	ENST00000559133.6 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant, NMD_transcript_variant	7/67	1
FBN1	ENST00000674301.2 linkuse as main transcript	c.687C>G	p.His229Gln	missense_variant, NMD_transcript_variant	7/68
FBN1	ENST00000537463.6 linkuse as main transcript	c.636+51C>G		intron_variant, NMD_transcript_variant		5

Frequencies

GnomAD3 genomes

AF:

0.0000131

AC:

AN:

152216

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251368

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135872

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:

0.00000342

AC:

AN:

1461890

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727246

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

AF:

0.0000131

AC:

AN:

152216

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74364

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000282

Hom.:

Bravo

AF:

0.0000151

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection

Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Apr 19, 2023	This missense variant replaces histidine with glutamine at codon 229 of the FBN1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with FBN1-related disorders in the literature. This variant has been identified in 1/251368 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	May 09, 2023	The p.H229Q variant (also known as c.687C>G), located in coding exon 6 of the FBN1 gene, results from a C to G substitution at nucleotide position 687. The histidine at codon 229 is replaced by glutamine, an amino acid with highly similar properties. This amino acid position is well conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Nov 27, 2023

This sequence change replaces histidine, which is basic and polar, with glutamine, which is neutral and polar, at codon 229 of the FBN1 protein (p.His229Gln). 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: 457255). 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 not expected to disrupt FBN1 protein function with a negative predictive value of 95%. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.12

BayesDel_addAF

Uncertain

0.024

BayesDel_noAF

Benign

-0.20

CADD

Benign

DANN

Benign

0.87

Eigen

Benign

-0.054

Eigen_PC

Benign

0.13

FATHMM_MKL

Uncertain

0.79

LIST_S2

Benign

0.78

M_CAP

Benign

0.059

MetaRNN

Benign

0.26

MetaSVM

Uncertain

-0.18

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.70

PROVEAN

Benign

-2.2

REVEL

Uncertain

0.39

Sift

Benign

0.57

Sift4G

Benign

0.32

Vest4

0.17

MutPred

0.53

Loss of catalytic residue at H229 (P = 0.0329);

MVP

0.66

MPC

1.2

ClinPred

0.73

GERP RS

4.5

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

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