Abstract:

Objective To analyze the clinical characteristics associated with prenatal diagnosis of FBN 1 gene mutations in a family. This study explores the correlation between gene mutations and their corresponding clinical phenotypes， emphasizing the significance of prenatal diagnosis in providing a foundation for subsequent follow?up and intervention. Methods Genomic DNA was extracted from the amniotic fluid of the fetus and the peripheral blood of the parents for trio?whole exome sequencing. The candidate variant identified was subsequently validated using Sanger sequencing. Results The pedigree comprised four generations and nine family members， with four individuals exhibiting slender limbs and toes. Among these， three showed congenital lens dislocation or subluxation. No abnormalities in the cardiovascular system were observed. Genetic testing of symptomatic individuals revealed a heterozygous mutation （c.6158G > T） in the FBN 1 gene. Conclusions The FBN 1 c.6158G > T （p.C2053F） mutation was identified as the pathogenic variant responsible for the condition in this family， exhibiting autosomal dominant inheritance. To our knowledge， this is the first reported case of the FBN 1 c.6158G > T （p.C2053F） mutation in China. Prenatal diagnosis can facilitate early confirmation of the condition and provide a foundation for subsequent interventions and follow?up care.

Key words: FBN1 gene, congenital isolated ectopia lentis, prenatal diagnosis, pedigree, infant