ABSTRACT
Congenital cataract is a challenging ophthalmological disorder which can cause severe visual loss. It can be diagnosed at birth or during the first year of life. Early diagnosis and treatment are crucial for the visual prognosis. It can be associated with various ocular and systemic abnormalities. Determining whether congenital cataract is isolated or associated with other pathology is an indispensable step for the prediction of potential vision as well as early diagnosis and treatment of conditions that can cause morbidity or mortality. Many genes have been identified in the molecular etiology of congenital cataract. Most mutations have been reported in the crystallin genes. Determination of the genetic cause may not only enable individualized genetic counseling but also help to identify concomitant ocular and/or systemic disorders depending on the characteristics of the genetic test used. Recently, next-generation sequencing in particular has become an evolving technology for determining the molecular etiology of congenital cataract and furthering our knowledge of the disease.
Keywords:
Genetics, congenital cataract, crystallin, lens, next-generation sequencing
Introduction
Congenital cataract is lens opacity that presents at birth or early in the postnatal period. It may be unilateral or bilateral. Because it occurs during early vision development, it causes serious vision loss and, more importantly, severe amblyopia. Follow-up and treatment are long-term and important, and an etiology cannot be identified for a substantial proportion of patients.1 For this reason, one of the main objectives of the Vision 2020: Right to Sight, a global initiative to eliminate preventable blindness worldwide, was to prevent causes of childhood blindness, including congenital cataract.2
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