This allele is a low mutating type with very few excision events (2b), however, sectors that are motley appear. The motley kernels, though they look like R r r, are proven to be R R. When the 2b is crossed to an En reporter allele, En activity cosegregates with 2b. Thus, the 2b allele is a low mutating En at the c2 locus. When motley germinals are backcrossed (x c2 c2), the low mutating type appears. The segregating pattern indicates that a separate independent factor converts the 2b pattern to a motley pattern. It seems that the 2b is autonomously mutable (En) at c2 and it is methylated, but from a near quiescent (2b) state shows a motley appearance. This is proven by testing with wx-m8 which shows sectoring when the motley (active) appears, but no sectoring when it is quiescent.
to the MNL 67 On-Line Index
Return to the Maize Newsletter Index
Return to the Maize Genome Database Page