At the Karolinska Institute, Stockholm, Sweden, Professor Karl-Gustaf Luening and his assistants are studying the effects of atomic radiation on the reproductivity of mice.
At the Karolinska Institute, Stockholm, Sweden, Professor Karl-Gustaf Luening and his assistants are studying the effects of atomic radiation on the reproductivity of mice. The Radiation-Genetics Department is directly responsible to the swedish Atomic Energy Commission.
Research on genetic mutation in some 20,000 mice - to obtain information on radiation effects on the human race - began two years ago when a pair of BCA mice were used to start a chain of generations of mice to be irradiated. Mice of the BCA type are the result of consistent inbreeding between the offspring of one pair, over more than 100 generations. In marked contrast to human beings, mice remain unaffected by this practice.
At the Institute, 125 male mice of every generation bred are selected when 60 days old and their reproductive organs and thus their chromosomes exposed to a radiation of 275 roentgen - a higher level of radioactivity than measured at Hiroshima. Female mice cannot be used for these tests since radiation sterilizes them.
Sperm cells of the irradiated male mice are examined before they reach maturity, and ten days later the next generation is bred. This process is repeated after 90 days.
The object of these tests is to determine possible genetic changes in successive generations. So far, after four generations, such changes have not occurred. Research has established, however, that irradiation decreases the reproductive capacity in mice. Definite further results may not be obtained for some time as mice bread only two generations per year.