This type of heritable cataract is progressive and has a variable phenotype both within and between families.  It is usually seen bilaterally in early childhood but may be congenital in onset.  Fine, dispersed, pulverulent opacities of the primary lens fibers are seen in the embryonic nucleus often with increased density at the ends of the Y suture at 12, 2, and 6 o'clock presenting a triangular appearance.  However, the entire nucleus may be opaque as well.  Zonular and posterior subcapsular opacities may appear later but there is considerable variation among patients and they may also appear in a stellate pattern.  The lamellar pattern consists of a zone of opacification around a clear embryonic nucleus.  There may be considerable difference in the rate of progression of the opacities among patients and even between the two eyes.

This may be among the most common type of congenital, autosomal dominant cataract.  The first family was reported in 1878 and the family data has been updated and reported several times since then.  The most recent reported pedigree consisted of 965 individuals in 9 generations.  Among the 70 individuals added, 56 had cataract surgery performed between the ages of 1 month and 26 years with a mean of 8 years.  However, some adults never had cataract surgery. 

Another family with early onset, progressive, autosomal dominant cataracts mapping to the same locus has been reported (see Maumenee, 1979) but the opacification involves the secondary lens fibers at the posterior pole.  These may be variants of the same condition.