Epistasis often results in modified dihybrid phenotypic rati

Epistasis often results in modified dihybrid phenotypic ratios. Assume that you obtain one such modified ratio, 9-7, with the gene pairs A and B involved. What would be a possible genotype for a phenotype that would be included with the 9 portion of the modified ratio? O aa bb O aa Bb O Aa bb O aa BB O Aa BB

Solution

1. Epistasis is the interaction of genes that are not alleles, in particular the suppression of the effect of one such gene by other. AaBB would be the possible genotype for 9 in ratio 9:7.

2. In genetics, a maternal effect occurs when the phenotype of an individual is determined by genotype of its mother. Option A is the correct answer.

3. Multifactorial traits are formed by the interaction of genes with the environment. Some examples of multifactorial traits are height, weight, eye color , etc., Hence, Option C is the correct answer.

4. Penetrance is defined as the percentage of individuals having particular genotype who expresses the expected phenotype. Option c is the correct answer.