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PKU Carriers
How Many Are in Your Hometown?
Author: 
David J. Grise 
Abstract:  In this interrupted case study, students read about a college student with phenylketonuria (PKU). Students learn how diet affects a person with PKU and how PKU is inherited. The case is designed to introduce introductory biology students to the HardyWeinberg Principle. Terms of the equation are related to phenotypes and genotypes mentioned in the case. Given the number of people in the population with PKU and assuming the population is in HardyWeinberg Equilibrium, students estimate the number of carriers for PKU in the population. Finally, students estimate the probability that a person from this population with PKU would have a child with PKU and the probability that a person from this population without PKU would have a child with PKU. 
Objectives: 

Keywords:  HardyWeinberg principle; inheritance; genotype frequency; carrier frequency; allele frequency; homozygous; heterozygous; population genetics; genetic disorder; phenylketonuria; PKU; phenylalanine; hydroxylase; PAH; gene mutation; founder effect 
Topical Area:  N/A 
Educational Level:  High school, Undergraduate lower division 
Formats:  
Type/Method:  Interrupted 
Language:  English 
Subject Headings:  Biology (General) Genetics / Heredity Molecular Biology 
Date Posted:  3/17/2011 
Date Modified:  N/A 
Copyright:  Copyright held by the National Center for Case Study Teaching in Science, University at Buffalo, State University of New York. Please see our usage guidelines, which outline our policy concerning permissible reproduction of this work. 
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