This mutation identifies a putative site for profibrillin to fibrillin processing, and is associated with isolated skeletal features of the Marfan syndrome, indicating that the FBN1 gene is one of the genes that determines height in the general population.
We describe here the identification of defined mutations in both alleles of the fibrillin gene (FBN1) in a compound-heterozygote Marfan syndrome (MFS) child who had a very severe form of MFS resulting in death from cardiac failure at the age of 4 mo.
Two novel mutations and a neutral polymorphism in EGF-like domains of the fibrillin gene (FBN1): SSCP screening of exons 15-21 in Marfan syndrome patients.
An extra cysteine in one of the non-calcium-binding epidermal growth factor-like motifs of the FBN1 polypeptide is connected to a novel variant of Marfan syndrome.
Interestingly, the neonatal MFS mutations are clustered in one particular region of FBN1, possibly providing new insights into genotype-phenotype comparisons.
While mutations causing classic manifestations of Marfan syndrome have been identified throughout the FBN1 gene, the six previously characterized mutations resulting in the severe, perinatal lethal form of Marfan syndrome have clustered in exons 24-32 of the gene.
In this study we screened all 65 exons of the fibrillin-1 gene in 20 Marfan syndrome families where at least two affected individuals were characterised and available for analysis, another 30 families with only one affected member available for analysis, and in 10 sporadic cases.
Fibrillin-1 mutations have also been found in several other related connective tissue disorders, such as severe neonatal Marfan syndrome, dominant ectopia lentis, familial ascending aortic aneurysm, isolated skeletal features of Marfan syndrome, and Shprintzen-Goldberg syndrome.
A third family cosegregates mild mitral valve prolapse syndrome with a mutation in FBN1 that can be functionally distinguished from those associated with the classic MFS phenotype.