Ethical Issues on Animal and Human cloning

Prof. P.C. Shaw (邵鵬柱教授 )Department of Biochemistry, CUHKHong Kong Bioethics Association

November 2009

複

製

人

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History of cloning

1952 Northern leopard frogs cloned.

1953 S tructure of DNA discovered.

History of cloning 1978 Louise, the first child

conceived through in vitro fertilization, was born.

1993 Human embryos were first cloned (artificial embryo twinning)

July 5, 1996 Dolly was born.

Photo from: www.cnn.com

Dolly – the first mammal cloned using mature cell Dolly the Lamb

in 1996 Method: Nuclea

r transfer Organization: R

oslin Institute at UK and PPL Therapeutics

Photo from Ming Pao 18th August 2002

Example of cloning

Cumulina the Mouse in 1998

Organization: University of Hawaii

Photo from Ming Pao 28th December 2002

Example of cloning

Cattle in 1998

Organization: Kinki University at Japan

Photo from Ming Pao 28th December 2002

Example of cloning

Mille, Christa, Alexis, Carrel and Dotcom the Pigs in 2000

Organization: PPL Therapeutics of UK

Photo from Ming Pao 28th December 2002

Example of cloning

Carbon Copy the Cat in 2002

Organization: Texas A & M University, USA

Photo from Ming Pao 23th January 2003

Example of cloning Generation of

Prometea, 2003

Organization: A research laboratory in Italy

Photo from Nature No.6949

Examples of cloning Cloning of

donkey, 2004, USA

Cloning of dog, 2005, Korea

Cloning of rhesus monkey, 2007, Oregon, USA http://jamaica-gleaner.com/gleaner/20050806/mind/mind3.html

http://www.pbs.org/newshour/bb/science/july-dec07/stemcells_11-15.html

Two methods of cloning

Embryo cloning 胚胎複製 - remove a cell from an embryo for developing into a separate embryo.

Adult cell cloning 成長細胞複製 - replace DNA/nucleus from a cell by another.

Two methods of cloning

Embryo cloning 胚胎複製 – do not know the characteristics of the offspring.

Adult cell cloning 成長細胞複製 – characteristics are almost the same as the nucleus donor.

How to generate Dolly?

Step 1.

Udder ( 乳腺 ) cells were taken from a donor sheep. Cells were then cultured to switch off their genes and become dormant.

Photo from www.bootstrike.com, www.nature.com

How to generate Dolly?Step 2.

Unfertilized egg cell was taken from another sheep. The nucleus was removed, leaving an empty egg.

Photo from www.pbs.org. www.nature.com, www.sciam.com

How to generate Dolly?Step 3.

The egg cell without nucleus was fused with the donor cell using a pulse of electricity. A second pulse started the cell division.

Photo from www.advancedcell.com. www.nature.com

How to generate Dolly?

Step 4.

After 6 days, the resulting embryo was implanted into another sheep (surrogate mother 代母 ).

Photo from www.pbs.org, www.nature.com

How to generate Dolly?

Step 5.

After gestation ( 妊娠 ), the surrogate mother gave birth to Dolly which was identical to the udder cell donor.

Photo from www.pbs.org

Advantages of animal cloning

Can produce animal with a desired trait, for Protein products, organs

Proliferate endangered animals

Cloning of endangered animal

Noah the Gaur ( 亞洲野牛 , an endangered species) in 2000

Organization: Advanced Cell Technology, USA Photo from Advanced Cell Technology (www.advancedcell.c

om)

Cloning of endangered animal Cloning of

woolly Mammoth ( 長毛象 )

Extinct 10,000 years ago

Is there any intact cell left?

From Mingpao 8/8/2003

Cloning of transgenic animal

Cloning of a cow containing mad cow disease resistant gene

In Shangdong, China

From Mingpao 28/4/2006

Concerns in animal cloning Technology complicated Survival rate of cloned

embryos low Overweighing of calves at

birth Breeders may want to keep

their animal unique Breeders may want to

create better offspring

Health of clonesFrom Ming Pao 27-Mar-2001

• Poor development of heart, lung and immune system

• Might have genetic disorder

Photo from MingpaoPhoto from Mingpao

Dolly gave birth to a female lamb in

1998, but Dolly later died of premature

aging in 2003.

Company for cloning pets Genetic Savings & Clone – established in

2000, produced the cloned cat, CC in 2001 Delivered the first commercially cloned

cat, Little Nicky in 2004 for US$50,000 Company closed in 2006 A new company BioArts International was

established for cloning dogs

Commercial pet cloning may not be a good investment Demand not high Competition from developing countries

Disregard of the IP issues Relaxed treatment of animals

The IP holder does not want to defense the IP rights

Outcome is unpredicted – cloning is not a mature techniques

Pressure from the society

Cloning Human

Cloning – two kinds Reproductive cloning – an

embryo is created and implanted into a woman’s womb to bring it to term.

Therapeutic cloning – an embryo is created in order to obtain cells from it.

Why clone human? Just an ‘unconventional’ means of

reproduction In vitro fertilization Surrogate mother Adoption

Study human development

Produce spare parts Test for genetic defect Increase chance of

pregnancy Produce two children at

the same time

Why clone human?

Preserve traits and talents

Extension of life in unusual circumstances One spouse sterile Homosexual

marriage

Why clone human?

Cloned embryos provide : Brain cells for disorders like Par

kinson ( 柏金遜 ) and Alzheimer’s disease ( 老年痴呆症 )

Pancreatic islet cells for diabetes ( 糖尿 )

Positive points of therapeutic cloning

Cloned embryos provide : Nerve cells for spinal cord da

mage ( 脊椎受損 ) Blood and bone marrow cells

for blood cell disorder ( 血液疾病 )

Positive points of therapeutic cloning

http://dels.nas.edu/bls/stemcells/types-of-stem-cells.shtml

Embryonic stem cells Adult stem cells

The use of stem cells to generate clones

http://www.geneticsandsociety.org/article.php?id=257

1. Creating an embryo through in vitro fertilization,

2. culturing ES cells derived from it to provide a sufficient population for the tricky task of inserting genes

3. extracting the nucleus of a successfully altered cell to construct a cloned embryo

4. The resulting offspring would have developed from a cell derived from an embryo created with an egg and a sperm, and "improved" in the laboratory.

Why not perform reproductive cloning?

Eugenic ( 優生 ) – to maximize certain traits intentionally

Reduce genetic diversity Use as substitute for organ Clone may have reduced life expectancy Clone may be abnormal

Why not perform reproductive cloning?

Lack of self-identity Replaceable Dominated by the

‘father’ or ‘mother’

Why not perform reproductive cloning?

Upset traditional family relationship Twin of the cell

donor? Relationship with its

brother and sister Relationship with

spouse of the cell donor

Human Reproductive Technology Bill香港人類生殖科技條例 (2000)

Not allow the followings: Replace nucleus o

f an embryo with nucleus of another cell

Clone an embryo Trading of embryo

Human cloning in China 人类辅助生殖技术与人类精子库相关技

术规范、基本标准和伦理原则 (Oct. 1, 2003) – by Ministry of Health

Prohibits surrogate mother Prohibits reproductive human cloning Prohibits donation of embryos Prohibits trading of eggs

                               

CLONAID™ was founded in February 1997, by

Raël, the leader of the Raelian MovementRaelian Movement, an international religious

organization, which claims that a human

extraterrestrial race, called the ElohimElohim, used

DNA and genetic engineering, to

scientifically create all life on Earth.

Adapted from Clonaid.com

雷爾教派倡導複製人研究。

Recent Development in Human Cloning

Clonaid claimed to give birth to ‘Eve’ on 26 December 2002

announced a second birth to a Dutch lesbian woman early in January 2003 and a third to a Japanese couple who "cloned their dead son killed in an accident", plus two others in late January

Recent Development in Human Cloning Korean Scientists led by Dr. Woo-suk Hwang

produced cloned human embryos (Science, Feb. 12, 2004) – later found to be fabricated

American scientist Panayiotis Zavos claimed to have cloned 14 human embryos and transferred 11 of them into the wombs of four women (April, 2009)

Recent Development in Human Cloning August 2004 - UK granted the first licence for

work toward therapeutic cloning. Nov. 2004 - Californians passed a $3 billion me

asure to create an Institute for Regenerative Medicine based on embryonic stem cell research.

Please consider ...... Would the views of animal and human

cloning differ among people with different religious believes?

Is embryo a living human? Since the use of stem cells for

therapeutic cloning is still in experimental stage, would the use of cells from embryo be acceptable?

How about using the embryos left over after in vitro fertilization?

Please consider ...... Is reproductive cloning a violation

of natural birth? How about the cloning of a

beloved one who dies accidentally? How about cloning for sterile

couples? Under what circumstances do you

want to make a copy of yourself?

End