ZRDCT Raxey1 and ZRDCT Rax+ mice were developed from the anophthalmic strain B described by Chase in 1941. The original animals from strain R were obtained from Little at The Jackson laboratory in 1938. Little selectively bred for anophthalmia by sibling matings, Chase continued the inbreeding to 21+ generations. Two sublines were established designated Be1 for the 98% eyeless group (Raxey1) and Be2 for the 96% normal group (Rax+) (Chase 1944). The donating investigator, Dr. Lois Laemle, indicates that this strain came from Chase through Dr. Kaiserman-Abramof. This strain did not come from Dr. Sidney Beck. It is not clear when the designation ZRDCT appeared. The strain was donated to The Jackson Laboratory in 2004.