Question 1.25

The type of albinism that arises with high frequency among Hopi Native Americans (discussed in the introduction to this chapter) is most likely oculocutaneous albinism type II, due to a defect in the OCA2 gene on chromosome 15. Do some research on the Internet to determine how the phenotype of this type of albinism differs from phenotypes of other forms of albinism in humans and the mutated genes that result in these phenotypes. Hint: Visit the Online Mendelian Inheritance in Man Web site (http://www.ncbi.nlm.nih.gov/omim/) and search the database for albinism.

Question 1.26

We now know a great deal about the genetics of humans, and humans are the focus of many genetic studies. What are some of the reasons humans have been the focus of intensive genetic study?

Question 1.27

Suppose that life exists elsewhere in the universe. All life must contain some type of genetic information, but alien genomes might not consist of nucleic acids and have the same features as those found in the genomes of life on Earth. What might be the common features of all genomes, no matter where they exist?

Question 1.28

Choose one of the ethical or social issues in parts a through e and give your opinion on the issue. For background information, you might read one of the articles on ethics marked with an asterisk in the Suggested Readings section for Chapter 1 at http://courses.bfwpub.com/pierce5e.

• a. Should a person’s genetic makeup be used in determining his or her eligibility for life insurance?
• b. Should biotechnology companies be able to patent newly sequenced genes?
• c. Should gene therapy be used on people?
• d. Should genetic testing be made available for inherited disorders for which there is no treatment or cure?

Question 1.29

A 45-year old woman undergoes genetic testing and discovers that she is at high risk for developing colon cancer and Alzheimer disease. Because her children have 50% of her genes, they also may be at an increased risk for these diseases. Does she have a moral or legal obligation to tell her children and other close relatives about the results of her genetic testing?

Question 1.30

Suppose that you could undergo genetic testing at age 18 for susceptibility to a genetic disease that would not appear until middle age and has no available treatment.

• a. What would be some of the possible reasons for having such a genetic test and some of the possible reasons for not having the test?
• b. Would you personally want to be tested? Explain your reasoning.