AIM:To analyze the causative gene mutation for Marfan syndrome(MFS)with autosomal dominant hereditary in a Chinese family in Liaoning Province,China.

METHODS: Venous blood was collected and candidate gene was selected to design primers according to the clinical phenotype. With genomic polymerase chain reaction(PCR)performed, the coding exons and their flanking intron in sequences of candidate gene were sequenced,DNA fragments separated by agarose gel electrophoresis and direct sequencing method was used to determine the pathogenic gene.

RESULTS:Phenotype of the proband was presented as ectopic lentis. Sequencing of the coding regions of FBN1 gene showed the presence of a heterozygous A→G transversion at nucleotide 640 in the 7 exon of FBN1 and the missense mutation made for Glycine into Serine(G214S).

CONCLUSION:A heterozygous mutation of FBN1 c.A640G(p.G214S)is responsible for the Marfan syndrome in the four generation Chinese pedigree.