This disorder has variable inheritance with the exception that complete nonpeneterance has not been documented. It is autosomal dominant heterozygous. A minute number of cases are speculated to be autosomal recessive. Marfan Syndrome is not sex-linked. Mechanism of the Disorder Marfan is caused by mutations of the FBN I involve skipping exons that encode the calcium binding epidermal growth factor.
Mutations can vary depending on the specific exons skipped.
Some skips are a premature termination codon in exon four. One of the mutations affects the synthesis, secretion, and matrix incorporation and deposition of the Fibrillin protein. This creates a dominant negative effect. I is a glycoporotein of the microfibrill. On occasion the microfibrill's formation is disorganized These collagens are a major structural component of connective tissue.