Identification of Three FBN1 Mutations in Chinese Patients with Typical or Incomplete Marfan Syndrome by Whole-Exome Sequencing

Abstract

Objective: The purpose of this work was to obtain the phenotypes and detect potential mutations in three Chinese patients with Marfan syndrome (MFS) or incomplete MFS phenotypes. Methods: Three unrelated patients with a definite or suspected clinical diagnosis of MFS and their family members were recruited for research. Genomic DNA was extracted from peripheral blood of these patients and their family members. All the exons were sequenced by next-generation sequencing and the variants were further validated by Sanger sequencing. The functional consequences of the mutations were analyzed with various genomic resources and bioinformatics tools. Results: Three FBN1 mutations were identified in the three patients, including one novel mutation (2125G > A) and two previously reported mutations (4786C > T and 6325C > T). It was interesting to note that the parents of these patients were normal as assessed by clinical features or genetic testing, but all these mutations were detected in their offspring, except for the variant 6325C > T. We also found that a few young members of the family of probands (proband 1 and proband 2) have exhibited no manifestations of MFS so far, although they carry the same disease-causing mutation. Conclusions: We found three FBN1 mutations in three unrelated Chinese families with MFS by genome sequencing, and the relationship between genotypes and phenotypes in MFS patients needs further exploration.