1. BT11.03: Evaluate therapeutic vs. reproductive cloning

2. Tuesday • What is an example of pharming? • A. Using transgenic animals to produce substances used in medicine • B. Using viruses to transfer genetic information • C. Improving livestock with transgenic research • D. Using transgenic mice to study cancer, MS and muscular dystrophy

3. History of cloning • Dolly the sheep – first cloned mammal in 1997*** • Very few scientists believe human cloning (reproductive cloning) should be permitted • Most scientists in favor of therapeutic cloning ***– the procedure used to produce embryonic stem cells that theoretically can be used to treat diseases

4. What is a clone? • Clone = precise genetic copy • Reproductive cloning is really somatic cell nuclear transfer (SCNT) • In therapeutic cloning, the embryo is not placed in a surrogate, but rather, undergoes cell division in the lab until it reaches blastocyst stage • There is currently no evidence of successful human cloning in the world***

5. Obstacles to reproductive cloning using animals • Success rate very low • Vast majority of problems occur during fetal development • Additional problems show up after birth and years later • “Large offspring syndrome” = cloned newborns 20-30% larger than usual, making it hard to deliver unborn babies

6. Embryonic and adult stem cells • Adult stem cells • Embryonic stem cells • Stem cells are important to medical researchers because they may be used to create perfectly matched tissue to treat an individual disease or disorder*** • Scientists may create a new human stem cell line if private funding resources are used***

7. Why would a person need an adult stem cell transfusion? • When a radiation treatment for cancer has destroyed the person’s stem cells***

8. Differences between reproductive cloning, therapeutic cloning, and stem cell research • Goal of reproductive cloning is to create a new organism, human or animal • Goal of therapeutic cloning is to produce embryonic stem cells • The purpose of performing embryonic stem cell research is to develop new and better ways to treat disease

9. Human stem cell research • 2001 legislation allowed federal funding of research using 64 existing human embryonic stem cells • Same legislation declared no federal funds for additional research.

10. Therapeutic potential of stem cells • Researchers must use existing human stem cell lines for research or find private funding sources • Creation of embryonic stem cells does not use fertilized egg • On the other hand, it does have the potential to become a living thing if transplanted into the uterus

11. Therapeutic potential of stem cells (continued) • Real advantage of stem cells – permits the production of perfect-match tissue • Scientists have found that embryonic stem cells pick up cues from neighboring cells and differentiate into that cell type • Scientists hope stem cells will be used to treat heart disease, Parkinson’s disease, other disorders of the nervous system