Question

What are complementary genes? Explain.

Answer 1

When one of two or more genes that when present together produces effects qualitatively distinct from the separate effect of any one of them, it is called as a complementary gene.

It can also be written as follows:

The complementary gene is a interaction of two dominant non inter-allelic gene in which each gene have its own effect but when come together to interact a new trait is developed and the Mendelian ratio 9:3:3:1 is changed to 9:7 due to complementation of both genes.