Translocation between pair nos. 1 and 12 chromosomes was noted in a female Lewis-strain rat. The short arm of the pair no. 1 of this rat was longer than the normal partner, while the long arm of the pair no. 12 was shorter than the normal one. The 1-12 translocation was transmitted to the offspring with the regular segregation ratio.
Particle volume distribution analysis method was applied to the immunologic agglutination of latex particles. By using monodisperse and stable latex particles, coated with antigen, agglutination caused by corresponding antibody was quantitatively proved. This method determined the presence of allospecific natural anti-IgG factor in a serum of non-immunized rabbit and anti-human IgG factor in healthy persons' sera.