Punnett Square

Describe the Punnett Square and what it used to predict. What are the limitations of the Punnett Square?

Mom is a carrier for hemophilia but does not have the disease.
Dad does not have hemophilia

Using the Punnett Square, answer the following questions:

  • What is the probability a female offspring developing hemophilia?
  • What is the probability of a female offspring being a carrier for hemophilia?
  • What is the probability of a male offspring developing hemophilia?
  • What is the probability of a male offspring being a carrier developing hemophilia?
  • What is the probability of any offspring developing hemophilia?
  • Explain why only some offspring would develop the disease?
  • If this were about Cystic Fibrosis, how would the responses be different to the questions in the Initial Post? Give a detailed explanation supporting your response.
  • Down Syndrome is another genetic disorder. Why is the Punnett Square not a good tool for predicting if offspring will have Down Syndrome? Why does the risk for Down’s Syndrome increase with maternal age?