NM_000138.5:c.3896C>T

Variant names:

• chr15-48481723-G-A
• rs774851476
• NM_000138.5:c.3896C>T

Variant summary

Our verdict is Benign. Variant got -13 ACMG points: 3P and 16B. PM1 PP2 BP6_Very_Strong BS1 BS2

The NM_000138.5(FBN1):​c.3896C>T​(p.Thr1299Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000626 in 1,613,562 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.000046 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000064 (0 hom.)
• Consequence: FBN1 NM_000138.5 missense
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:14
• Conservation: PhyloP100: 8.05

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 Benign. Variant got -13 ACMG points.

• PM1: In a domain EGF-like 21; calcium-binding (size 41) in uniprot entity FBN1_HUMAN there are 10 pathogenic changes around while only 2 benign (83%) in NM_000138.5
• 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.
• BP6: Variant 15-48481723-G-A is Benign according to our data. Variant chr15-48481723-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 316375.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr15-48481723-G-A is described in Lovd as [Likely_benign].
• BS1: Variant frequency is greater than expected in population amr. gnomad4_exome allele frequency = 0.0000643 (94/1461540) while in subpopulation AMR AF= 0.00177 (79/44722). AF 95% confidence interval is 0.00145. There are 0 homozygotes in gnomad4_exome. There are 39 alleles in male gnomad4_exome subpopulation. Median coverage is 30. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 7 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FBN1	NM_000138.5	c.3896C>T	p.Thr1299Met	missense_variant	Exon 32 of 66	ENST00000316623.10	NP_000129.3
FBN1	NM_001406716.1	c.3896C>T	p.Thr1299Met	missense_variant	Exon 31 of 65		NP_001393645.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FBN1	ENST00000316623.10	c.3896C>T	p.Thr1299Met	missense_variant	Exon 32 of 66	1	NM_000138.5	ENSP00000325527.5

Frequencies

GnomAD3 genomes AF: 0.0000460 AC: 7 AN: 152022 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000459

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: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000294 AC: 74 AN: 251336 Hom.: 0 AF XY: 0.000214 AC XY: 29 AN XY: 135824

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00208

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: 0.000163

GnomAD4 exome AF: 0.0000643 AC: 94 AN: 1461540 Hom.: 0 Cov.: 30 AF XY: 0.0000536 AC XY: 39 AN XY: 727092

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00177

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000989

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000460 AC: 7 AN: 152022 Hom.: 0 Cov.: 32 AF XY: 0.0000135 AC XY: 1 AN XY: 74244

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000459

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000109 Hom.: 0

Bravo AF: 0.0000604

ExAC AF: 0.000247 AC: 30

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:14

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Benign:3

Aug 28, 2019

Color Diagnostics, LLC DBA Color Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jun 05, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Jun 17, 2020

Ambry Genetics

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This alteration is classified as likely benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Marfan syndrome Benign:2

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases allowed determination this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -

May 30, 2024

All of Us Research Program, National Institutes of Health

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not specified Benign:2

Feb 13, 2023

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

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 25, 2018

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

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. -

Stiff skin syndrome Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Weill-Marchesani syndrome Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Geleophysic dysplasia Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Acromicric dysplasia Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

not provided Benign:1

Mar 01, 2025

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

FBN1: BS1 -

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

Nov 19, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Ectopia lentis 1, isolated, autosomal dominant Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). No publications were found based on this search. Allele frequency data from public databases was too high to be consistent with this variant causing disease. Therefore, this variant is classified as benign. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.34
BayesDel_addAF	Uncertain	0.053	T
BayesDel_noAF	Pathogenic	0.30
CADD	Pathogenic	32
DANN	Pathogenic	1.0
Eigen	Pathogenic	0.93
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.96	D
M_CAP	Pathogenic	0.80	D
MetaRNN	Uncertain	0.62	D
MetaSVM	Pathogenic	1.0	D
PrimateAI	Uncertain	0.78	T
PROVEAN	Pathogenic	-5.1	D
REVEL	Pathogenic	0.82
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0010	D
Vest4		0.74
MutPred		0.71		Loss of methylation at K1300 (P = 0.0416);
MVP		0.94
MPC		1.4
ClinPred		0.19	T
GERP RS		5.4

Splicing

Name	Calibrated prediction	Score	Prediction
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

Publications

LitVar

Other links and lift over

dbSNP: rs774851476; hg19: chr15-48773920;