Zea mays ssp. Mutant kernels are sometimes reduced in size. The mutation is expressed when plants carrying Dap1 are crossed as females, but not as males. Dap1 shows reduced transmission through both the male and female, and is most likely homozygous lethal in the zygote or embryo. Classification varies from good to poor for the kernel.
Viability is normal for the heterozygote and embryo lethal for the homozygote.