Marfan Syndrome: Whole-Exome Sequencing Reveals De Novo Mutations, Second Gene and Genotype-Phenotype Correlations in the Chinese Population.

Marfan syndrome (MFS) is a dominant monogenic disease caused by mutations in fibrillin 1 (FBN1). Cardiovascular complications are the leading causes of mortality among MFS. In this study, a whole-exome sequencing of MFS in the Chinese population was conducted to investigate the correlation between FBNI gene mutation and MFS. Forty-four low-frequency harmful loci were identified for the FBN1 gene in HGMD database. In addition, 38 loci were identified in the same database that have not been related to MFS before. A strict filtering and screening protocol revealed two patients of the studied group have double mutations in the FBN1 gene. The two patients harboring the double mutations expressed a prominent, highly pathological phenotype in the affected family. In addition to the FBN1 gene, we also found that 27 patients had mutations in the PKD1 gene, however these patients did not have kidney disease, and 16 of the 27 patients expressed aortic related complications. Genotype-phenotype analysis showed that patients with aortic complications are older in the family, aged between 20-40 years.