The Marfan Syndrome (MFS), the most common disorder of connective tissue, is characterized by ocular, cardiovascular, and skeletal abnormalities. Inherited as an autosomal dominant trait it has a prevalence of about 1 per 10,000 population. Median lifespan is approximately half of normal due primarily to cardiovascular complications. Short of clinical phenotype, there is presently no diagnostic tool to identify affected individuals. The clinical features of MFS are also shared by other conditions in different combinations and at various degrees. The search for the MFS gene product has been carried out relatively unabated, by numerous investigators, for more than forty years. Our immunohistochemical studies have implicated fibrillin, the major component of the elastin-associated microfibrils, in MFS etiology. Very recently, we have confirmed this causal association using molecular and genetic techniques. We cloned the fibrillin gene, mapped it to chromosome 15, and, for the first time, established direct linkage between this gene and MFS. Serendipitously, we cloned two additional genes, thus demonstrating the fibrillin is molecularly heterogeneous. Most significantly, we established linkage between one of these fibrillin genes, which resides on chromosome 5, and an MFS-related condition, congenital contractural arachnodactyly (CAA). This original and unexpected finding of linkage between distinct fibrillin genes and phenotypically related syndromes implies that defects in these newly discovered matrix components are the cause of this rather common group of connective tissue disorders. We will now extend these studies by generating full size cDNAs of fibrillins on both chromosomes 5 and 15, and by identifying mutations in selected MFS and CCA patients. The cDNA data will provide the very first insight into the structure, relationship, and evolution of these poorly characterized group of glycoproteins. the genetic studies will elucidate the function of these macromolecules in connective tissue physiology. Together, these studies will establish the framework for understanding how altered fibrillin metabolism translates into the phenotypic spectrum of MFS and related syndromes.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29HL048126-02
Application #
3473825
Study Section
Pathobiochemistry Study Section (PBC)
Project Start
1992-04-01
Project End
1997-03-31
Budget Start
1993-04-01
Budget End
1994-03-31
Support Year
2
Fiscal Year
1993
Total Cost
Indirect Cost
Name
University of Nebraska Medical Center
Department
Type
Schools of Medicine
DUNS #
City
Omaha
State
NE
Country
United States
Zip Code
68198
Godfrey, M; Raghunath, M; Cisler, J et al. (1995) Abnormal morphology of fibrillin microfibrils in fibroblast cultures from patients with neonatal Marfan syndrome. Am J Pathol 146:1414-21
Wang, M; Mata, J; Price, C E et al. (1995) Prenatal and presymptomatic diagnosis of the Marfan syndrome using fluorescence PCR and an automated sequencer. Prenat Diagn 15:499-507
Schaefer, G B; Godfrey, M (1995) Quantitation of fibrillin immunofluorescence in fibroblast cultures in the Marfan syndrome. Clin Genet 47:144-9
Godfrey, M; Cisler, J; Geerts, M L et al. (1995) Fibrillin immunofluorescence in pseudoxanthoma elasticum. J Am Acad Dermatol 32:589-94
Godfrey, M (1994) From fluorescence to the gene: the skin in the Marfan syndrome. J Invest Dermatol 103:58S-62S
Godfrey, M; Vandemark, N; Wang, M et al. (1993) Prenatal diagnosis and a donor splice site mutation in fibrillin in a family with Marfan syndrome. Am J Hum Genet 53:472-80