The paternal chromosome carries the linked alleles, C1-I Ds Sh1 Bz1 Wx1. The maternal chromosomes carry the recessive alleles, C1 sh1 bz1 wx1. In the presence of an active Ac transposable element, the defective Ds element breaks the chromosome between C1 and Sh1, thereby causing the loss of the dominant inhibitory C1-I allele on the distal part of the chromosome, allowing color to be expressed. This is seen by the formation of a large sector on the left outlined with the dark rim. In the endosperm, the sticky ends of the broken chromatids fuse to form a bridge with subsequent losses of proximal markers as the bridge breaks asymmetrically. This is seen by the loss of the Bz1 allele, responsible for dark pigment color, in the upper half of the sector on the left.