Indirect genotype analysis as a tool for diagnosis of Marfan syndrome

Marfan syndrome (MFS) is an autosomal dominant disorder of connective tissu e characterized by skeletal, ocular and cardiovascular manifestations. The disease is caused by mutations in the FBN1 gene, encoding fibrillin, an imp ortant component of elastic fibers. Diagnosis of Marfan syndrome is current ly based on detailed clinical examination and/or mutation analysis in the f ibrillin gene. Clinical expression varies widely both among and within fami lies, rendering clinical diagnosis extremely difficult. In this study, we p erformed segregation analysis of allelic DNA polymorphisms to support diagn osis of Marfan syndrome. This type of genotype analysis is a useful, additi onal diagnostic tool for families with Marfan syndrome and provides increme ntal information of diagnosis or exclusion of Marfan syndrome based on clin ical findings.