Somatic recombination in the dikaryon ofCoprinus lagopus

Abstract

A technique based upon auxotrophic mutants and recessive suppressor genes has been used to select for somatic recombinants in the dikaryon ofCoprinus lagopus. Both haploid and disomic nuclei with a reassortment of chromosomes from the two component nuclei of the dikaryon were found. The presence of the disomics indicates that the recombination process is one of fusion of nuclei with a gradual haploidization by loss of chromosomes at mitotic divisions. An extensive test for crossing-over in theAchromosome failed to give an unambiguous crossover recombinant, but it produced a stock with a normalAchromosome and a fragment of the chromosome.