Abstract: Abstract Objiective: Marfan syndrome (MFS), an autosomal dominant inherited disease, has variable clinical manifestations typically affecting the cardiovascular, ocular and skeletal systems. Two causative genes for MFS have been demonstrated so far: Fibrillin-1 (FBN1) and TGFBR2 gene. This study aims to indentify the disease causing gene in a Chinese family with autosomal dominant MFS. Method:The detailed clinical examinations were performed and documented on each patient.DNA samples were collected from all participants.Exclusive mapping and mutation screening of FBN1 gene by direct sequencing were carried out. Results:After exclusion of the TGFBR2 locus by linkage analysis, significant linkage was found with markers of the FBN1 locus in the 15q21.1 region in both families. We then identified a novel mutation of FBN1,which is a premature termination codon (PTC) mutation. Conclusion:This server mutation correlates with the server phenotype, specifically the cardiovascular malformation, in the family.

Key words: Fibrillin-1, Linkage analysis, Marfan Syndrome, Mutation