Mouse Genome Informatics
involves: 129S4/SvJae * C57BL/6J
phenotype observed in females
phenotype observed in males
N normal phenotype

Nuclear cataracts in Gja8tm1Paul/Gja8tm1Paul mice

• early postnatal eye and lens growth is severely deficient and pathological changes become evident at P7
• EM measurements of fiber diameter in the equatorial regions of wild-type and mutant lenses show no significant differences in fiber size, suggesting fewer lens fibers due to a reduced rate of cell division
• at 2 weeks of age, mutant lenses display an irregular and diffuse nuclear opacity not present in control lenses
• by 6 months of age, mutant lenses show a fine particulate precipitate confined to the nucleus, which is typical of zonular pulverulent cataracts
• in addition, a sharply defined line of unknown nature is found in the inner cortical region of the mutant lens
• lenses dissected from adult male homozygotes are 46% smaller than lenses from control littermates
• at P0, mutant eye mass is identical to that of controls but is decreased 18% by P7
• by P14, the mutant eye mass is only 68% that of control, and remains constant for at least 4 months
• notably, the eye growth rate continues to decrease for 1 week after the lens growth rate has stabilized
• at P0, mutant lens mass is identical to that of controls but is reduced to only 56% that of control by P7, and remains constant thereafter
• at P7, mutant lenses show a large clear zone composed of fiber cells that lack the normal eosinophilic staining in the nuclear region
• however, at E16.5, mutant lenses appear normal in terms of size and integrity relative to control lenses
• dye injection studies revealed no significant differences in lens intercellular communication at developmental stages prior to cataract formation
• eyes dissected from adult male homozygotes are 32% smaller than eyes from control littermates
• however, no significant differences are observed in overall postnatal growth, average mass of adult mutant animals, their kidneys or testes relative to controls

Mouse Models of Human Disease
Cataract 1, Multiple Types; CTRCT1 116200 J:50894