What is the Difference Between Complementary and Supplementary Genes?

The main difference between complementary and supplementary genes lies in their ability to produce independent traits and their interactions in the F2 generation phenotypic ratio. Here are the key differences:

Independent Traits: Complementary genes are a pair of non-allelic genes that interact to produce a particular phenotypic trait, but neither of them can produce the trait independently. In contrast, supplementary genes are a pair of non-allelic genes where only one is able to express its effect independently, and the interaction of the two genes modifies the expression of the independently expressing gene.
F2 Generation Phenotypic Ratio: The phenotypic ratio in the F2 generation for complementary genes is generally 9:7, while the phenotypic ratio for supplementary genes is generally 9:3:4.

In summary, complementary genes require the presence of both genes to express a specific trait, while supplementary genes have one gene that can express its effect independently. The F2 generation phenotypic ratios are also distinct for each type of gene interaction.

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What is the Difference Between Complementary and Supplementary Genes?

Comparative Table: Complementary vs Supplementary Genes

The main difference between complementary and supplementary genes lies in their ability to produce traits independently. Here is a table summarizing the differences between complementary and supplementary genes:

Feature	Complementary Genes	Supplementary Genes
Definition	Genes that complement the effects of each other, and the presence of both genes is necessary to produce the trait.	Genes that interact, but one dominant gene can express its trait without the presence of the other gene.
Interaction	The action of complementary genes is complementary, where the presence of each gene is necessary to produce the trait.	One dominant gene expresses without the presence of the other gene, but the second gene needs the presence of the first gene for its expression.
Phenotypic Ratios	Complementary genes have a phenotypic ratio of 9:7.	Supplementary genes have a phenotypic ratio of 9:3:4.
Examples	The purple flower color of the sweet pea and the red eye color in Drosophila are examples of complementary genes.	No specific examples found in the search results.

In summary, complementary genes require the presence of both genes to produce a trait, while supplementary genes have one dominant gene that can express its trait independently.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.