In analyzing the early stages on the origin of maize, one would use a teosinte background segregating the key trait alleles of maize that are symbolically coded to indicate the direction of divergence away from the wild type teosinte. These variants toward maize would be expected to be recessive and only much later to evolve a background where they could be expressed as dominants. When the background is relatively fixed, the frequency for a given phenotype may be scored under a modified type of symbol with a sub-postscript of t for teosinte or m for maize representing the background of dominance modifiers relative to the observed phenotype within the segregation as in Table 1.
Table 1. The genetic symbols for teosinte-maize key traits indicating dominance and wild type reversal.
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