1. Embryo Cloning One embryo splits into 2 identical embryos
May occur from 2 cell stage up to 14 days
After 14 days results in conjoined twins
Happens naturally and artificially

2. Natural Embryo Cloning
1 in 75 pregnancies spontaneously clone
Blastula (ball of cells) splits in 1st 14 days
Monozygotic twins =
clones

3. Natural Triplets – 1 in 8,100 births
Natural Quadruplets – 1 in 729,000
All quads - 1 in 571,787
Multiple Births Canada (MBC):
90% of quad pregnancies result from fertility assistance. At $100,000 a try
The incidence of quad birth rose more than 400% in the last quarter of the 20th century

4. Dr. Papiernik said at his hospital, half the babies in neonatal intensive care are from fertility-enhanced pregnancies. The cost of such care has led countries with national health care like England and France to restrict the number of embryos placed during in vitro fertilization to three.
Multiples spend up to 10 weeks in neonatal intensive care at $7,000 a day

5. Artificial Twinning
Embryo cloning where embryos from desirable parents encouraged to spilt into clones.
Embryos implanted into surrogate mothers.
Ex. Genetically engineered low fat pork
High quality beef cattle

6. Adult Cloning DNA from adult it placed in an egg
Called Nuclear Transfer
1) nucleus of egg is removed
2) nucleus from adult cell placed in the egg
3) egg shocked (chemicals or electricity)
4) shocked egg reacts like it was fertilized
5) growing embryo implanted in surrogate
mother.

7. Cloning
1 A microneedle
2 The microneedle has emptied the sheep egg of its own nucleus.
3 DNA from a donor cell is about to be deposited in the enucleated egg.
4 An electric spark will stimulate the egg to enter mitotic cell division.
the first cloned sheep
Fig. 13-9, p.214

8. Impacts, Issues: Goodbye Dolly
Ian Wilmut was the first to produce a cloned sheep, which he named Dolly
Dolly experienced health problems similar to other mammals cloned from adult DNA

9. Goodbye Dolly
Fig. 13-1a, p.206

10. Impacts, Issues: Goodbye Dolly
The risk of defects in clones is huge
Possible benefit – patients in desperate need of organ transplants
Genetically modified cloned animals may produce organs that human donors are less likely to reject
Cloning humans – ethical?

11. Impacts, Issues Video D:\PowerLecture\Media\PowerLectures\chapter13\animations\csDolly.html
Goodbye Dolly

12. D:\PowerLecture\Media\PowerLectures\chapter13\animations\csDolly.html

14. Cloning Making a genetically identical copy of an individual
Researchers have been creating clones for decades
These clones were created by embryo splitting

15. Cloning
How Dolly was created

16. Dolly: Cloned from an Adult Cell
Showed that differentiated cells could be used to create clones
Sheep udder cell was combined with enucleated egg cell
Dolly is genetically identical to the sheep that donated the udder cell

17. Dolly: Cloned from an Adult Cell
Fig. 13-9, p.214

18. Cloning vs. Sexual Reproduction

19. More Clones
Mice
Cows
Pigs
Goats
Guar (endangered species)

20. Fig , p.215

21. Fig , p.215

22. Therapeutic Cloning SCNT – Somatic Cell Nuclear Transfer
Transplant DNA of an adult somatic cell into a stem cell (undifferentiated cell)

23. 1: under the microscope, the DNA of the patient is introduced into the egg, through a microscopic glass tube.
After 5-6 days, the egg has developed into a ball of cells, the blastocyst, of which is removed the inner cell mass.
After culture in a plastic dish, the inner cell mass has grown to aggregates which contain the embryonic stem cells that match the patients immunologic profile.

24. Theraputic Cloning by Nuclear transfer of patients DNA

25. Cloned cells will not be rejected by the patient's immune system.
These embryonic stem cells can now be used to generate cells and tissues for the patient.

26. Embryonic Stem Cells
Sources of stem cells….
unwanted embryos from fertility treatment
Embryos created by nuclear transfer from egg

27. Congress twice passed the Stem Cell Research Enhancement Act with strong bipartisan support
both times President Bush vetoed the bill.
President Barack Obama lifted the restrictions on federal funding for ESCR on March 9, 2009 by an Executive Order.