Send to

Choose Destination
Mol Syndromol. 2013 Mar;4(3):125-35. doi: 10.1159/000347163. Epub 2013 Feb 28.

The c.7409G>A (p.Cys2470Tyr) Variant of FBN1: Phenotypic Variability across Three Generations.

Author information

Department of Pathology and Laboratory Medicine, University of British Columbia, B.C., Canada ; Department of Child and Family Research Institute, University of British Columbia, B.C., Canada.


Marfan syndrome is an autosomal dominant connective tissue disorder caused by mutations in the fibrillin gene FBN1, which encodes an extracellular matrix glycoprotein. Major features of Marfan syndrome occur in the ocular, cardiovascular, and skeletal systems as well as in the dura mater. Approximately 60% of known disease-causing mutations are missense mutations of single amino acid residues. Effects on the cardiovascular system are classically associated with mutations in exons 24-32 of the 65 FBN1 exons and many, though not all, reports associate missense mutations in exons 59-65 with a mild cardiovascular phenotype. Here we present 5 related individuals among whom a c.7409G>A (p.Cys2470Tyr) missense variant in exon 59 of FBN1 is associated with significant cardiovascular features. The index case also had an apparently de novo 46,XX,del(5)(q33.1q33.3) deletion on chromosome 5. This family demonstrates skeletal, dermatological and neurological features consistent with Marfan syndrome but lacks significant ophthalmological findings to date. These findings suggest that FBN1 C-terminal missense mutations may not confer the ophthalmological features of Marfan syndrome, but they also confer a more significant risk for cardiovascular pathology than that suggested by previous studies. Furthermore, clinical data from this family supports the previously reported association of dural ectasia with C-terminal mutations.


Cardiovascular phenotype; Diagnostic criteria; FBN1; Marfan syndrome; Novel mutation

Supplemental Content

Full text links

Icon for S. Karger AG, Basel, Switzerland Icon for PubMed Central
Loading ...
Support Center