rs140582

Positions:

• chr15-48495596-A-G
• chr15-48495596-A-T

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_000138.5(FBN1):​c.2420-8T>C variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000258 in 1,614,058 control chromosomes in the GnomAD database, including 3 homozygotes. 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 Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0015 (1 hom., cov: 33)
  • Exomes 𝑓: 0.00013 (2 hom.)
• Consequence: FBN1 NM_000138.5 splice_region, intron
• Scores: Splicing: ADA: 0.00004267
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:16
• Conservation: PhyloP100: 1.87

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 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.63).
• BP6: Variant 15-48495596-A-G is Benign according to our data. Variant chr15-48495596-A-G is described in ClinVar as [Likely_benign]. Clinvar id is 137302.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr15-48495596-A-G is described in Lovd as [Benign].
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.0015 (229/152344) while in subpopulation AFR AF= 0.00529 (220/41580). AF 95% confidence interval is 0.00472. There are 1 homozygotes in gnomad4. There are 103 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 229 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FBN1	NM_000138.5	c.2420-8T>C		splice_region_variant, intron_variant		ENST00000316623.10	NP_000129.3
FBN1	NM_001406716.1	c.2420-8T>C		splice_region_variant, intron_variant			NP_001393645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10	c.2420-8T>C		splice_region_variant, intron_variant		1	NM_000138.5	ENSP00000325527.5

Frequencies

GnomAD3 genomes AF: 0.00145 AC: 220 AN: 152226 Hom.: 1 Cov.: 33

Gnomad AFR AF: 0.00509

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

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: 0.00191

GnomAD3 exomes AF: 0.000271 AC: 68 AN: 250934 Hom.: 0 AF XY: 0.000111 AC XY: 15 AN XY: 135726

Gnomad AFR exome AF: 0.00379

Gnomad AMR exome AF: 0.000174

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.000128 AC: 187 AN: 1461714 Hom.: 2 Cov.: 32 AF XY: 0.000106 AC XY: 77 AN XY: 727156

Gnomad4 AFR exome AF: 0.00436

Gnomad4 AMR exome AF: 0.000246

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000580

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.000348

GnomAD4 genome AF: 0.00150 AC: 229 AN: 152344 Hom.: 1 Cov.: 33 AF XY: 0.00138 AC XY: 103 AN XY: 74498

Gnomad4 AFR AF: 0.00529

Gnomad4 AMR AF: 0.000196

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: 0.00189

Alfa AF: 0.000927 Hom.: 0

Bravo AF: 0.00162

Asia WGS AF: 0.00115 AC: 4 AN: 3478

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:16

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Benign:3

Benign, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Oct 25, 2018	- -
Benign, criteria provided, single submitter	clinical testing	CHEO Genetics Diagnostic Laboratory, Children's Hospital of Eastern Ontario	May 08, 2023	- -
Likely benign, criteria provided, single submitter	clinical testing	Illumina Laboratory Services, Illumina	Jun 14, 2016	- -

not provided Benign:3

Likely benign, criteria provided, single submitter	not provided	Breakthrough Genomics, Breakthrough Genomics	-	- -
Likely benign, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	Jul 13, 2023	- -
Likely benign, no assertion criteria provided	clinical testing	Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center	-	- -

not specified Benign:2

Benign, criteria provided, single submitter	clinical testing	GeneDx	Jan 12, 2014	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, no assertion criteria provided	clinical testing	Genome Diagnostics Laboratory, University Medical Center Utrecht	-	- -

Ectopia lentis Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Marfan syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Stiff skin syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

MASS syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Weill-Marchesani syndrome Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Geleophysic dysplasia Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

Acromicric dysplasia Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jun 14, 2016

- -

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

Benign, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 06, 2024

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.63
CADD	Benign	9.3
DANN	Benign	0.76

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000043
dbscSNV1_RF	Benign	0.0080
SpliceAI score (max)		0.020		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

Other links and lift over

dbSNP: rs140582; hg19: chr15-48787793;