FBN1 gene: fibrillin 1

Curated reports relevant to this gene

Aortic Aneurysm
- Familial Thoracic Aortic Aneurysm and DissectionAutosomal dominant
  Inherited widening and tearing of the thoracic aorta, caused by changes in genes such as ACTA2, MYH11, MYLK, LOX, PRKG1, MFAP5 and THSD4.
  - ClinGen rates the link definitive
  - 1 GenCC submitter rates it definitive or strong
  What knowing changes
  Knowing about it supports regular aortic imaging, blood pressure control and timely preventive surgery, and screening of relatives.
Marfan Like Syndromes
- Marfan SyndromeAutosomal dominant
  A disorder of the connective tissue. Connective tissue provides strength and flexibility to structures throughout the body such as bones, ligaments, muscles, walls of blood vessels, and heart valves. Marfan syndrome affects most organs and tissues, especially the skeleton, lungs, eyes, heart, and the large blood vessel that distributes blood from the heart to the rest of the body (the aorta). It is caused by mutations in the FBN1 gene, which provides instructions for making a protein called fibrillin-1. Marfan syndrome is inherited in an autosomal dominant pattern. At least 25% of cases are due to a new (de novo) mutation. Treatment is based on the signs and symptoms in each person.
  - 4 GenCC submitters rate it definitive or strong
  - On the ACMG secondary findings list
- Marfanoid-progeroid-lipodystrophy syndromeAutosomal dominant
  Specific FBN1 variants causing a tall, slender build with near-total lack of body fat and an aged appearance.
  - 1 GenCC submitter rates it definitive or strong

Inheritance

Autosomal dominant: One changed copy, from either parent, is enough. A parent who has one passes it on to each child with a one-in-two chance.

How FBN1 is laid out

Coding sequence
Untranslated region
Intron
Direction of transcription
Known disease-causing sites
Stretches short reads find hard
Variants with a page

Exons of the gene's MANE Select transcript (release v1.5), from NCBI and EMBL-EBI, on the GRCh38 reference genome.

Chromosome bands from UCSC's GRCh38 ideogram (2022-10-29).

Nearby genes from Ensembl release 116, on GRCh38.

Exons make up 11.6 kb of the gene's 237.4 kb; 8,616 of those bases code for the protein.

How a genome test reads FBN1

2,135

positions in FBN1 where ClinVar classes a change as pathogenic or likely pathogenic

None of them falls in a region short reads find hard.

A whole genome covers all 237.4 kb of FBN1, introns included, not only the 11.6 kb of exons.

Variants with a page (509)

The FBN1 variants with a page here, most review stars first. Each page describes ClinVar's public record of the variant, never a result.

Variant	HGVS c.	Exon or intron	Position (GRCh38)	ClinVar classification	Review status
c.1A>C		Exon 2	48,644,769	Pathogenic	3 stars out of 4 reviewed by expert panel
c.989-1G>C		Intron 9	48,520,818	Pathogenic	3 stars out of 4 reviewed by expert panel
c.4583-5A>G		Intron 37	48,468,107	Likely pathogenic	3 stars out of 4 reviewed by expert panel
c.5065+2_5065+3insT		Intron 41	48,463,896	Pathogenic	3 stars out of 4 reviewed by expert panel
c.6453C>T		Exon 53	48,437,004	Pathogenic	3 stars out of 4 reviewed by expert panel
c.7204+1G>T		Intron 58	48,427,566	Pathogenic	3 stars out of 4 reviewed by expert panel
c.7330+3_7330+6del		Intron 59	48,425,732	Likely pathogenic	3 stars out of 4 reviewed by expert panel
C67R	c.199T>C	Exon 3	48,613,058	Likely pathogenic	3 stars out of 4 reviewed by expert panel
C210Y	c.629G>A	Exon 7	48,537,718	Likely pathogenic	3 stars out of 4 reviewed by expert panel
C304Y	c.911G>A	Exon 9	48,526,207	Likely pathogenic	3 stars out of 4 reviewed by expert panel

See all 509 FBN1 variants →

Traits linked to FBN1

The Human Phenotype Ontology lists these as features of the rare conditions FBN1 can cause. Each trait's page lists the other genes linked to it.

Abnormality of head or neck

Show 42 more traits

Abnormality of the cardiovascular system

Show 38 more traits

Abnormality of limbs

Show 35 more traits

Abnormality of the musculoskeletal system

Show 33 more traits

Abnormality of the eye

Show 25 more traits

Abnormality of the nervous system

Show 10 more traits

Abnormality of the respiratory system

Show 8 more traits

Abnormality of the integument

Show 5 more traits

Growth abnormality

Show 2 more traits

Abnormality of the digestive system

Show 1 more trait

Incisional hernia

Abnormality of the ear

Abnormality of prenatal development or birth

Abnormality of the genitourinary system

Abnormality of the immune system

Abnormality of blood and blood-forming tissues

Laboratory abnormality

External links

Gene records

Transcript

Protein

Variants

Clinical

Where this comes from

HGNC: the gene's symbol, name, other symbols and location.
MANE Select v1.5, from NCBI and EMBL-EBI: the transcript, its exons and coding sequence.
GenCC and ClinGen, released 2026-10-16: which conditions the gene is linked to, and how strongly.
The ACMG secondary findings list, SF v3.2.
ClinVar and the GIAB stratifications: known disease-causing sites, and the regions short reads find hard.
The Human Phenotype Ontology, release 2026-09-01: the traits linked to the gene. Find out more at hpo.jax.org.
Data release 2026.10.16-c6eea6bf.

Cite this page

APA

Dante Labs. (n.d.). FBN1 gene: fibrillin 1. Retrieved 17 October 2026, from https://dantelabs.com/genes/fbn1

Vancouver

Dante Labs. FBN1 gene: fibrillin 1 [Internet]. [cited 17 October 2026]. Available from: https://dantelabs.com/genes/fbn1