Congenital cataract is both an ophthalmologic and social problem. The role of hereditary has shown it forms 8.25% of all congenital cataracts. A genetic analysis in humans is not possible due to generation times and small numbers of progeny. Mouse congenital cataract mutants Cat-Fraser (Cat-Fr) and Lop provide an excellent system to study inheritance of cataract. They also provide a method to undertake in vivo and in vitro research on the growth, replication and gene expression in lenses of the cataractous mice. Breeding experiments are presently in progress to assign a specific chromosome for the dominant inherited Cat-Fr mouse. Chromosome 10 has already been mapped for the Lop cataract. Experimental chimeras formed from the aggregation of preimplantation embryos of cataractous and non-cataractous mice will attempt to """"""""rescue"""""""" the abnormal lens defects. Blastocyst injection of cataractous cells will analyze the contribution of these cells to normal tissue. In vitro studies on clonal populations of mouse lens epithelial cells derived from Cat-Fr, Lop and normal lenses, will characterize morphological changes with replication and growth patterns, e.g. nuclear and cell size, distribution of microtubules, intermediate filaments and microfilaments, synthesis of specific lens proteins. Those in vitro parameters which are found to be associated with certan phases of the normal lens cells replication and/or growth pattern, will serve as a base line for similar studies on the lens epithelial cells derived from the cataractous mice. Somatic cell hybridization and micromanipulation techniques will be employed to study the possibility of manipulating the in vitro parameters.
