15-48446702-G-T

Variant names:

• chr15-48446702-G-T
• rs577301285
• NM_000138.5:c.5788+4C>A

Variant summary

Our verdict is Likely benign. The variant received -4 ACMG points: 0P and 4B. BP4_Strong

The NM_000138.5(FBN1):​c.5788+4C>A variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000912 in 1,425,726 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000091 (0 hom.)
• Consequence: FBN1 NM_000138.5 splice_region, intron
• Scores: Splicing: ADA: 0.0003534
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:11 B:3
• Conservation: PhyloP100: -0.567
• Publications: 0 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):

• Marfan syndrome

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, ClinGen, Orphanet, Genomics England PanelApp
• familial thoracic aortic aneurysm and aortic dissection

  Inheritance: Unknown, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• Acromicric dysplasia

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

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

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

ACMG classification

Our verdict: Likely_benign. The variant received -4 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.72).

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

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN1	NM_000138.5	MANE Select	c.5788+4C>A		splice_region intron	N/A	NP_000129.3
	FBN1	NM_001406716.1		c.5788+4C>A		splice_region intron	N/A	NP_001393645.1	P35555

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FBN1	ENST00000316623.10	TSL:1 MANE Select	c.5788+4C>A		splice_region intron	N/A	ENSP00000325527.5	P35555
	FBN1	ENST00000559133.6	TSL:1	n.5788+4C>A		splice_region intron	N/A	ENSP00000453958.2	H0YND0
	FBN1	ENST00000537463.6	TSL:5	n.*1551+4C>A		splice_region intron	N/A	ENSP00000440294.2	F6U495

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000239 AC: 6 AN: 251020 AF XY: 0.0000221

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000869

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000264

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000912 AC: 13 AN: 1425726 Hom.: 0 Cov.: 27 AF XY: 0.0000112 AC XY: 8 AN XY: 711734

African (AFR) AF: 0.00 AC: 0 AN: 32670

American (AMR) AF: 0.0000672 AC: 3 AN: 44634

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25900

East Asian (EAS) AF: 0.00 AC: 0 AN: 39528

South Asian (SAS) AF: 0.00 AC: 0 AN: 85580

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53234

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5690

European-Non Finnish (NFE) AF: 0.00000926 AC: 10 AN: 1079380

Other (OTH) AF: 0.00 AC: 0 AN: 59110

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000662 Hom.: 0

Bravo AF: 0.0000227

EpiCase AF: 0.0000546

EpiControl AF: 0.00

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	2	1	Marfan syndrome (3)
-	1	1	Familial thoracic aortic aneurysm and aortic dissection (2)
-	1	1	not provided (2)
-	1	-	Acromicric dysplasia (1)
-	1	-	Ectopia lentis (1)
-	1	-	Geleophysic dysplasia (1)
-	1	-	Marfan syndrome;C4707243:Familial thoracic aortic aneurysm and aortic dissection (1)
-	1	-	MASS syndrome (1)
-	1	-	Stiff skin syndrome (1)
-	1	-	Weill-Marchesani syndrome (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.72
CADD	Benign	0.10
DANN	Benign	0.58
PhyloP100		-0.57
Mutation Taster		=77/23	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00035
dbscSNV1_RF	Benign	0.018
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

Other links and lift over

dbSNP: rs577301285; hg19: chr15-48738899;