Congenital blindness refers to a group of diseases and conditions occurring in childhood or early adolescence of below 16 years old, which, if left untreated, result in blindness or severe visual impairment that are likely to be permanent blindness later in life. Congenital blindness is a hereditary disease and can be cured by gene therapy. Visual loss in children or infant can occur either at the stage of prenatal (during the time of conception or intrauterine period) or postnatal stage (during birth). A variety of causes can promote congenital blindness but the most concern and highest cause of it is a genetic mutation. 60% of congenital blindness are contributed from prenatal stage and another 40% are contributed from inherited disease. However, most of the congenital blindness cases sh