Factors regulating the degree and extent of experimental chimaerism in the mouse

The degree of chimaerism of the coat, bone marrow and cornea in mouse chimaeras obtained by aggregation of an albino inbred embryo of A strain with an A X CBA-T6T6 hybrid was investigated. Out of 21 individuals born, 18 were chimaeras. Statistically significant correlation has been demonstrated between chimaerism of the coat, bone marrow and the cornea. The contribution of the two components appears to be affected by two factors: first, variable participation of the two components inthe embryonic ectoderm of the chimaeric egg cyclinder, and second, the rate of proliferation of the two cell lines. A photometric method is described which permits the quantitative evaluation of coat chimaerism. The method is sensitive and reliable.