Pattern of offspring distribution according to genotype (i.e. the genetic constitution determining the phenotype of an organism)
The genotypic ratio describes the number of times a genotype would appear in the offspring after a test cross. For example, a test cross between two organisms with same genotype, Rr, for a heterozygous dominant trait will result in offspring with genotypes: RR, Rr, and rr. And in this example, the predicted genotypic ratio is 1:2:1.