Identification of Three Novel FBN1 Mutations and Their Phenotypic Relationship of Marfan Syndrome

Marfan syndrome (MS), a connective tissue disorder that affects ocular, skeletal, and cardiovascular systems, is caused by heterozygous pathogenic variants in FBN1. To date, over 1800 different pathogenic variants have been reported. In the present study, FBN1 sequence analysis was performed in a family and two unrelated patients with MS. Three novel pathogenic variants were detected. Two of these variants [c.6610T>C; p.(Cys2204Arg) and c.1956T>G; p.(Cys652Trp)], which affect a cysteine residue, were associated with MS with ectopia lentis, whereas the mutation causing a premature stop codon [c.2506delA; p.(Ser836ValfsX10)] leads to a classical MS of a milder phenotype. We anticipate that the three novel pathogenic variants identified in this study will provide further support for the clinical relevance of variants in the large FBN1 gene.