Common regulation of recombination at the amination-1 and histidine-2 loci in Neurospora crassa.

Recombination between alleles is reduced by rec-3+ at the am-J locus and by rec-x+ at the his-2 locus. The two recombination genes are both in the same region of the left arm of linkage group I between acr-3 and arg-3. All known stocks are either rec-3 rec-x or rec-3+ ree-x+. Recombination between ree-3 arid ree-x is less than 0·143%, with 95% probability. The evidence suggests that the two ree genes are the same, although they act on unrelated loci.