Breeding a pigmented strain of rats with tapetoretinal degeneration

When Royal College of Surgeons (RCS) rats are bred with Wistar albinos the offspring are deeply pigmented and have normally functioning retinas. From this second generation, various breeding possibilities exist. In the course of successive cross-breedings one can obtain albinos, tan striped (RCS type) or pigmented animals, any one of which may be normal, carrier or affected. The skin pigmentation trait and that of retinal degeneration are independently inherited and follow autosomal recessive Mendelian laws. However normals for ERG studies vary with skin pigmentation. It is suggested that only one group should be chosen and preferably the pigmented variety.