Mapping the genes that made maize.

George Beadle proposed that the striking morphological differences between cultivated maize and its probable wild progenitor (teosinte) were initiated by a small number of mutations with large effects on adult morphology. Recent genetic analyses using molecular markers provide some support for this view and show where in the maize genome the putative loci are likely to be located. This work sets the stage for fine-scale linkage mapping of these genomic regions and the eventual cloning of the genes involved in this remarkable evolutionary transformation.