THE PRODUCTION OF HOMOZYGOUS DEFICIENT TISSUES WITH MUTANT CHARACTERISTICS BY MEANS OF THE ABERRANT MITOTIC BEHAVIOR OF RING-SHAPED CHROMOSOMES

This lengthy article stemmed from McClintock's discovery of ring chromosomes in 1932 and research she conducted on the gene bm1, or brown midrib, after returning to the University of Missouri in 1938. McClintock concluded that the extent of variegation in a mature plant was proportional to the size of the ring that was sometimes lost at cell division.