Journal of Clinical and Experimental Ophthalmology
Open Access

Abstract

Genetic Analysis of a Family with a Novel Type I Fibrillinopathy

James A Eadie, John C Hart Jr and Les I Siegel

Background: This study describes a novel polymorphism in the Fibrillin gene (FBN1) and the associated unique Type I Fibrillinopathy phonotypic variant found in a single family. Clinical data were taken at a single academic institution while blood samples were sent for commercially available sequencing.
Methods: The proband of the study was referred to the authors with ectopia lentis (EL). A careful family history revealed several other family members with zonular instability detected at the time of cataract surgery. A thorough workup for known causes of EL uncovered a novel polymorphism in the FBN1 gene. A pedigree was devised and, medical records and genetic testing was obtained on eight additional family members. Retrospective analysis of clinical information and family history data were combined with prospective genetic analysis of the available cohort family members.
Results: The novel misprint mutation c.730T>C in the FBN1 gene was detected in all three family members with confirmed EL at the time of cataract surgery. In addition, this misprint was detected in 3 of 6 offspring of known carriers who had not yet undergone cataract surgery.
Conclusions: In our analysis of this single family we describe a novel Type I Fibrillinopathy. This phenotypic presentation is unique in that the zonular insufficiency in this family does not manifest until the time of cataract surgery. The presence of this disease entity provides a possible explanation for idiopathic zonular weakness encountered in what is expected to be routine ocular surgery.