Dihybrid cross

The idea of a dihybrid cross came from Gregor Mendel when he observed pea plants that were either yellow or green and either round or wrinkled.

Crossing of two heterozygous individuals will result in predictable ratios for both genotype and phenotype in the offspring.

Gregor Mendel was an Austrian-Czech monk who bred peas plants in his monastery garden and compared the offspring to figure out inheritance of traits from 1856-1863.

The expected phenotypic ratio of 9:3:3:1 can be broken down into: In the example pictured to the right, RRYY/rryy parents result in F1 offspring that are heterozygous for both R and Y (RrYy).

[4] Another example is listed in the table below and illustrates the process of a dihybrid cross between pea plants with multiple traits and their phenotypic ratio patterns.

This is a dihybrid cross of two heterozygous parents. The traits observed in this cross are the same traits that Mendel was observing for his experiments. This cross results in the expected phenotypic ratio of 9:3:3:1.