Study on the genotype and clinical phenotype of a family with isolated ectopia lentis / 安徽医科大学学报

ABSTRACT

Objective @#To identify possible associated genetic variants and characterise the clinical presentation of isolated ectopia lentis (IEL) .@*Methods @#Forty - eight members with 5 generations of an IEL family were enrolled in this study. Peripheral blood samples of all members were collected , and clinical manifestations were observed through physical examination and routine ophthalmological examination. Whole⁃exome sequencing (WES) was performed for two patients to identify disease⁃causing variants. The target variants were verified by Sanger sequencing in family members and 200 normal controls. Then , candidate variants were verified using Sanger sequencing in family members and 200 healthy controls. SIFT , PolyPhen and MutationTester were used to predict the protein function. @*Results @#A total of 13 IEL patients in this family which inherited in an autosomal dominant pattern. The mean age at disease onset was 51. 5 years. The main clinical phenotype of this ICE was characterised by ectopia lentis which anterior inclinated to the anterior chamber. As the anterior chamber became shallow , and the angle of the chamber became narrow , and eventually resulted in the secondary glaucoma. A heterozygous missense variantin the fibrillin gene⁃1 (FBN1) gene (c. 3463G > A) was identified by WES , which was present in all patients but was absent in 200 healthy controls. SIFT , PolyPhen and MutationTester predicted that the variant affected protein function.@*Conclusion @#This IEL family is characterized by secondary glaucoma as the first symptom which is caused by ectopia lens with inclination. The c. 3463G > A of FBN1 gene may be the pathogenic mutation leading to IEL in this family.