Consequently, a test cross can help determine whether a dominant phenotype is homozygous or heterozygous for a specific allele. Diploid organisms, like humans, have two alleles at each genetic ...

In its simplest form, a test cross is an experimental cross of an individual organism of dominant phenotype but unknown genotype and an organism with a homozygous recessive genotype (and phenotype).

To generate a tissue specific knockout mouse, researchers breed a mouse bearing a Cre transgene under a tissue- or cell-type specific or inducible promoter (A) with a homozygous floxed mouse (B). The ...