chr15-48613073-G-C

Variant names:

• chr15-48613073-G-C
• NM_000138.5:c.184C>G

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1 PM2 PM5 PP2 PP3

The NM_000138.5(FBN1):​c.184C>G​(p.Arg62Gly) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R62C) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: FBN1 NM_000138.5 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.00

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 Likely_pathogenic. Variant got 8 ACMG points.

• PM1: In a disulfide_bond (size 9) in uniprot entity FBN1_HUMAN there are 4 pathogenic changes around while only 1 benign (80%) 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 chr15-48613073-G-A 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, 0.828

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN1	NM_000138.5	c.184C>G	p.Arg62Gly	missense_variant	Exon 3 of 66	ENST00000316623.10	NP_000129.3
FBN1	NM_001406716.1	c.184C>G	p.Arg62Gly	missense_variant	Exon 2 of 65		NP_001393645.1
FBN1	NM_001406717.1	c.184C>G	p.Arg62Gly	missense_variant	Exon 3 of 9		NP_001393646.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10	c.184C>G	p.Arg62Gly	missense_variant	Exon 3 of 66	1	NM_000138.5	ENSP00000325527.5
FBN1	ENST00000559133.6	n.184C>G		non_coding_transcript_exon_variant	Exon 3 of 67	1		ENSP00000453958.2
FBN1	ENST00000537463.6	n.184C>G		non_coding_transcript_exon_variant	Exon 3 of 31	5		ENSP00000440294.2
FBN1	ENST00000674301.2	n.184C>G		non_coding_transcript_exon_variant	Exon 3 of 68			ENSP00000501333.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	29
DANN	Uncertain	1.0
Eigen	Uncertain	0.66
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.83	D
MetaSVM	Uncertain	0.19	D
PrimateAI	Uncertain	0.58	T
PROVEAN	Pathogenic	-4.8	D
REVEL	Uncertain	0.60
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.0020	D
Vest4		0.71
MutPred		0.62		Gain of glycosylation at S61 (P = 0.0433);
MVP		0.82
MPC		1.6
ClinPred		0.99	D
GERP RS		5.1

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr15-48905270;