Source: Reginald Crundall Punnett, DNA from the Beginning

Predicting the genotypes and phenotypes of an offspring in genetic crosses can sometimes be difficult. A Punnett square is a graphic organizer that can simplify the process. Punnett squares use probability to help determine the possible genotypes and phenotypes combinations in a genetic cross.

The technique was created by a British geneticist, Reginald Punnett. In 1905, Punnett published a textbook titled “Mendelism,” which included the technique. The Punnett square is still used today.

Click on the next button to begin the animation.

Watch the following video that discusses how to set up a Punnett square.