Paramutation in maize

Abstract

Mostly about Ac and Ds; esp. action at bz (See also CIW54). Modifiers of Spm action -- One controls type of a1-m1 action in the absence of Spm (recessive in presence of Spm). Another enhances frequency of occurrence of a1-m1 mutations, but only in presence of Spm Third comprises 2 "complementary elements, independently located in the chromosome complement." Effects observed in absence of Spm. Interaction of controlling elements adds a new level of complexity, a "second level of integration"