cataract, pulverant, juvenile-onset(redirected from CCA4)
cataract, pulverant, juvenile-onsetA usually bilateral form (OMIM:610202) of cataract with peripheral bluish and white pulverulent (dust-like) opacities, which can be found in any part of the lens. The phenotype shows significant intra- and interfamilial variation, both in the distribution of the cataract and the degree of opacification. Some patients also have microcornea and bilateral iris colobomas in addition to the cataract. Visual acuity is mildly reduced in childhood, but with time, lens extraction is required.
Fusiform cavities between lens fibres containing dark-staining granular material. The opacifications are arranged in concentric layers with occasional central lesions arranged radially. The opacities occur in the superficial layers of the foetal nucleus, as well as the adult nucleus of the lens.
Defects of MAF, which encodes a protein that plays a role in embryonic lens fibre cell development, cause pulverant cataract juvenile-onset.