OMIM ID:
Cataracts, Congenital Zonular Pulverulent 3
Alternate Names
Defective Genes
Clinical Characteristics
Ocular Features
Bilateral dust-like lens opacities are diagnosed at a median age of 5 years but have been seen at 6 months of age. These affect the embryonal, fetal, and infantile nucleus and are often surrounded by snowflake- or needle-like opacities throughout the lens cortex. The dust-like particles may be multicolored and impart a haze to the lens. Evidence for progression is suggested by the fact that about half of such affected patients require cataract surgery as adults. No other ocular abnormalities are present.
There is considerable phenotypic heterogeneity.
Systemic Features
No systemic abnormalities are associated.
Genetics
Inheritance
Heterozygous mutations in GJA3 (13q11) seem to be responsible for the opacities. For another somewhat similar form of autosomal dominant congenital cataract see Cataracts, Congenital Zonular Pulverulent 1 (116200).
Pedigree
Autosomal dominant
Autosomal dominant disorders require only one mutation for the disease to be expressed. Since an affected parent has two chromosomes, only one of which has the mutant gene, parents can expect that half (50%) of their children will receive that one and inherit the disease. It is common for individuals that inherit the mutation, however, to not have evidence of the disease (nonpenetrance).
Autosomal dominant inheritance leads to a vertical pattern of transmission