Congenital cataracts cause 10 to 30% of all blindness in children, with one-third of cases estimated to have a genetic cause (summary by Bu et al., 2002). Mutations in the HSF4 gene have been found to cause multiple types of cataract, which have been described as infantile, lamellar, zonular, nuclear, anterior polar, stellate, and Marner-type. The preferred title for this entry was formerly 'Lamellar Cataract,' with 'Cataract, Marner Type; CAM; CTM' an included title.

Hyperferritinemia-cataract syndrome is a disorder characterized by an excess of an iron storage protein called ferritin in the blood (hyperferritinemia) and tissues of the body. A buildup of this protein begins early in life, leading to clouding of the lenses of the eyes (cataracts). In affected individuals, cataracts usually develop in infancy, rather than after age 60 as typically occurs in the general population. Cataracts that are not removed surgically cause progressive dimming and blurriness of vision because the clouded lenses reduce and distort incoming light.\n\nAlthough the hyperferritinemia in this disorder does not usually cause any health problems other than cataracts, the elevated ferritin levels in the blood can be mistaken for a sign of certain liver disorders. These conditions result in excess iron in the body and may be treated by blood-drawing. However, individuals with hyperferritinemia-cataract syndrome do not have an excess of iron, and with repeated blood draws will develop reduced iron levels leading to a low number of red blood cells (anemia). Therefore, correct diagnosis of hyperferritinemia-cataract syndrome is important to avoid unnecessary treatments or invasive test procedures such as liver biopsies.

Mutations in the GJA8 gene have been found to cause several types of autosomal dominant cataract, which have been described as congenital, zonular pulverulent, nuclear progressive, nuclear pulverulent, stellate nuclear, nuclear total, total, and posterior subcapsular. Cataract associated with microcornea, sometimes called the cataract-microcornea syndrome, is also caused by mutation in the GJA8 gene. Before it was known that mutation in the GJB8 gene caused multiple types of cataract, this entry was titled 'Cataract, zonular pulverulent, 1,' with the symbols CZP1, CZP, and CAE1.

Mutations in the VIM gene have been found to cause multiple types of congenital cataract, which have been described as congenital, pulverulent, and posterior polar.

Bestrophinopathies, the spectrum of ophthalmic disorders caused by pathogenic variants in BEST1, are typically characterized by retinal degeneration. The four recognized phenotypes are the three autosomal dominant disorders: Best vitelliform macular dystrophy (BVMD), BEST1 adult-onset vitelliform macular dystrophy (AVMD), and autosomal dominant vitreoretinochoroidopathy (ADVIRC); and autosomal recessive bestrophinopathy (ARB). Onset is usually in the first decade (except AVMD in which onset is age 30 to 50 years). Slow visual deterioration is the usual course. Choroidal neovascularization can occur in rare cases. ADVIRC is also associated with panophthalmic involvement including nanophthalmos, microcornea, hyperopia, and narrow anterior chamber angle with angle closure glaucoma.

Mutations in the CRYBB1 gene have been found to cause multiple types of cataract, which have been described as congenital nuclear, congenital nuclear with anterior and posterior Y-suture and polar opacities, and pulverulent. The preferred title/symbol for this entry was formerly 'Cataract, Congenital Nuclear, Autosomal Recessive 3; CATCN3.'