Student Version


Name: ____________________________             Date: ________________

Cystic Fibrosis Activity:  Understanding the inheritance and expression of an autosomal recessive trait

GenScope File:


1.      Jean and Phil have a daughter, Kelly, who has cystic fibrosis.

Is it possible that her brother, Jake, has the disease, too?
What are the chances that he does have the disease? (25%, 50%, 75%)

Explain how you know.

2.       If Kelly marries a person who is normal and a non-carrier, will all of her children have the disease?    How do you know?

3.       Scott, from the F2 generation, marries Nicole and they have two children, one with cystic fibrosis and the other normal.  What are Nicole's genes for the cystic fibrosis trait?

4.       If Eric were able to take the medical history of his girl friends, what should he look for in the genetic makeup of a wife to ensure that none of their children would have cystic fibrosis?  Can he be sure that none of his grandchildren will have cystic fibrosis?

[ Table of Contents ] [ Previous Activity: Blood Type ] [ Next Activity: Scales and Plates ]

GenScope, A project of The Concord Consortium.
Copyright © 1998, All rights reserved. Inquiries regarding GenScope can be sent to