Discussion:
Genetic Disorders
1. Explain why teratogens are difficult to identify.
2. Explain why a woman carrying the gene for hemophilia can produce two hemophiliac sons when she is mated to a normal male.
3. Under what conditions does a female acquire an X-linked recessive disorder?
4. The pedigree for Queen Victoria of England, a carrier of hemophilia A, shows the transmission to some of her descendants, including members of many royal families in Europe, such as Russia and Spain, but not Germany. Hemophilia A does not affect anyone in the present British royal family. Can you explain why hemophilia A has disappeared from one family and appeared in others?
5. Which of the following can be identified by an abnormal karyotype?
a. Sickle cell disease
b. Cystic fibrosis
c. Monosomy X
d. Tay-Sachs disease
e. Huntington's disease