A 2-Year-Old Child with Bilateral Ectopis Lentis and a Novel FBN1 Gene Variant Cys129Ser

Marfan syndrome and dominant ectopia lentis are part of type 1 fibrillinopathies that are caused by FBN1 pathogenic variants. Making a diagnosis could be challenging due to the clinical overlap between these disorders. The revised Ghent criteria used for Marfan syndrome diagnosis helped in resolving some of the confusion, especially in younger children. We report on a case of bilateral ectopia lentis in a 2-year-old child with a normal echocardiogram. FBN1 sequencing revealed a novel likely pathogenic variant described as c.385T > A (p.Cys129Ser). The patient's father also has a history of bilateral ectopia lentis and his genetic analysis detected the same FBN1 variant as the proband.