Question

Assume that a cross is made between two organisms that are both heterozygous for a gene that shows incomplete dominance. What genotypic ratio is expected in the offspring?

Answer 1

Answer:

Genotypic ratio: 1 homozygous for parental trait : 2 heterozygous : 1 homozygous for other parental trait

Explanation:

Incomplete dominance is a non-mendelian type of inheritance in which one allele of a gene portrays Incomplete dominance over the other allele, hence, they combine to form a third phenotype that is a blending of both parental phenotypes. A very good example of incomplete dominance gene is that of flower colour in snapdragon plants.

One allele of the flower colour gene codes for RED while the other codes for WHITE. However, an heterozygous intermediate phenotype (PINK) is formed as F1 offspring when both parents are crossed.

If the F1 heterozygous offsprings are self-crossed i.e. two heterozygous offsprings, four possible offsprings will be produced with the genotypic ratio 1:2:1, which means that 1/4 of the offsprings will be homozygous for one of the parental traits, 2/4 will be heterozygous for both alleles, 1/4 will be homozygous for the other parental trait.

Answer 2

Answer:

1:2:1

Explanation: