NM_000138.5:c.1175C>G

Variant names:

• chr15-48516335-G-C
• rs534127494
• NM_000138.5:c.1175C>G

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 1P and 6B. PP2 BP4 BP6 BS1

The NM_000138.5(FBN1):​c.1175C>G​(p.Pro392Arg) variant causes a missense change. The variant allele was found at a frequency of 0.0000149 in 1,613,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P392A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.000092 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0000068 (0 hom.)
• Consequence: FBN1 NM_000138.5 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2 B:1
• Conservation: PhyloP100: 5.30
• Publications: 7 publications found

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 Gene-Disease associations (from GenCC):

• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Marfan syndrome

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, ClinGen, G2P, PanelApp Australia, Orphanet, Ambry Genetics
• Acromicric dysplasia

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Ambry Genetics
• progeroid and marfanoid aspect-lipodystrophy syndrome

  Inheritance: AD Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
• stiff skin syndrome

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• Weill-Marchesani syndrome 2, dominant

  Inheritance: AD Classification: STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae)
• geleophysic dysplasia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• isolated ectopia lentis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• neonatal Marfan syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Weill-Marchesani syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• ectopia lentis 1, isolated, autosomal dominant

  Inheritance: AD Classification: LIMITED Submitted by: G2P
• Shprintzen-Goldberg syndrome

  Inheritance: AD, Unknown Classification: LIMITED, NO_KNOWN Submitted by: ClinGen, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• 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 Marfan syndrome, Weill-Marchesani syndrome 2, dominant, progeroid and marfanoid aspect-lipodystrophy syndrome, geleophysic dysplasia, Shprintzen-Goldberg syndrome, stiff skin syndrome, familial thoracic aortic aneurysm and aortic dissection, isolated ectopia lentis, ectopia lentis 1, isolated, autosomal dominant, Acromicric dysplasia, neonatal Marfan syndrome, Weill-Marchesani syndrome.
• BP4: Computational evidence support a benign effect (MetaRNN=0.36617172).
• BP6: Variant 15-48516335-G-C is Benign according to our data. Variant chr15-48516335-G-C is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 654549.
• BS1: Variant frequency is greater than expected in population amr. GnomAd4 allele frequency = 0.000092 (14/152230) while in subpopulation AMR AF = 0.00085 (13/15296). AF 95% confidence interval is 0.000502. There are 0 homozygotes in GnomAd4. There are 13 alleles in the male GnomAd4 subpopulation. Median coverage is 32. This position passed quality control check.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000138.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN1	NM_000138.5	MANE Select	c.1175C>G	p.Pro392Arg	missense	Exon 11 of 66	NP_000129.3
	FBN1	NM_001406716.1		c.1175C>G	p.Pro392Arg	missense	Exon 10 of 65	NP_001393645.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN1	ENST00000316623.10	TSL:1 MANE Select	c.1175C>G	p.Pro392Arg	missense	Exon 11 of 66	ENSP00000325527.5
	FBN1	ENST00000559133.6	TSL:1	n.1175C>G		non_coding_transcript_exon	Exon 11 of 67	ENSP00000453958.2
	FBN1	ENST00000674301.2		n.1175C>G		non_coding_transcript_exon	Exon 11 of 68	ENSP00000501333.2

Frequencies

GnomAD3 genomes AF: 0.0000920 AC: 14 AN: 152112 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000851

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000320 AC: 8 AN: 250242 AF XY: 0.0000443

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.000116

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000354

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000684 AC: 10 AN: 1461586 Hom.: 0 Cov.: 33 AF XY: 0.00000963 AC XY: 7 AN XY: 727108

African (AFR) AF: 0.00 AC: 0 AN: 33454

American (AMR) AF: 0.000112 AC: 5 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39692

South Asian (SAS) AF: 0.00 AC: 0 AN: 86252

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53368

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5694

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1111904

Other (OTH) AF: 0.0000166 AC: 1 AN: 60372

GnomAD4 genome AF: 0.0000920 AC: 14 AN: 152230 Hom.: 0 Cov.: 32 AF XY: 0.000175 AC XY: 13 AN XY: 74436

African (AFR) AF: 0.00 AC: 0 AN: 41518

American (AMR) AF: 0.000850 AC: 13 AN: 15296

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3468

East Asian (EAS) AF: 0.00 AC: 0 AN: 5180

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10614

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2114

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.000102

ExAC AF: 0.0000330 AC: 4

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Marfan syndrome Uncertain:1

Apr 25, 2024

All of Us Research Program, National Institutes of Health

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This missense variant replaces proline with arginine at codon 392 of the FBN1 protein. Computational prediction is inconclusive regarding the impact of this variant on protein structure and function (internally defined REVEL score threshold 0.5 < inconclusive < 0.7, PMID: 27666373). To our knowledge, functional studies have not been reported for this variant. This variant has been reported in an individual affected with unexplained sudden cardiac death (PMID: 25447171). This variant has been identified in 8/250242 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.

not specified Uncertain:1

Aug 26, 2019

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: FBN1 c.1175C>G (p.Pro392Arg) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 3.2e-05 in 250242 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1175C>G has been reported in the literature in an individual who died of sudden cardiac death, with no-conclusive cause (Campuzano_2014). This report does not provide an unequivocal conclusion about association of the variant with Marfan Syndrome. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014. Based on the evidence outlined above, the variant was classified as uncertain significance.

Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection Benign:1

Sep 25, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Benign	0.0018	T
BayesDel_noAF	Uncertain	-0.010
CADD	Uncertain	24
DANN	Benign	0.88
Eigen	Uncertain	0.27
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.90	D
M_CAP	Uncertain	0.10	D
MetaRNN	Benign	0.37	T
MetaSVM	Benign	-0.46	T
PhyloP100		5.3
PrimateAI	Uncertain	0.56	T
PROVEAN	Uncertain	-3.6	D
REVEL	Uncertain	0.52
Sift	Benign	0.62	T
Sift4G	Benign	0.23	T
Vest4		0.52
MutPred		0.47		Gain of catalytic residue at P392 (P = 0.0695)
MVP		0.84
MPC		0.60
ClinPred		0.19	T
GERP RS		5.5
Mutation Taster		=79/21	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

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

Other links and lift over

dbSNP: rs534127494; hg19: chr15-48808532;