bioethics, stem cells & cloning

Stem Cells & Cloning 3/23/05

Stem Cells, Cloning & Bioethics

Bioethics as a basis for decision-making

This PPT has been produced as a modification of Steven G. Gilbert’s (PhD, DABT. www.asmalldoseof.org ) work to suit

theVCAA study design for VCE Biology curriculum

Year 12 BiologyUnit 3

Area of study 1: Molecules of LifeBIOETHICS


Why Bioethics?


Current Bioethical Issues

Check the local news paper Stem cells (state, national, international) Genetically Engineered Organisms Knowing your genes In vitro fertilization – choosing your child's

genes and characteristics Global warming Chemicals exposures – human health Environmental health


"A thing is right when it tends to preserve the integrity, stability, and beauty of the biotic community. It is wrong when it tends otherwise." -

Aldo Leopold, 1949, A Sand County Almanac

The First Bioethicist

---------- 1887 - 1948 ----------

Aldo Leopold


“An ethic, ecologically, is a limitation on freedom of action in the struggle for

existence”Aldo Leopold

Limits on Freedom


Technical Solutions

“It is our considered professional judgment that

this dilemma has no technical solution.”

The Tragedy of the CommonsBy Garrett Hardin, Science, 1968


Problems – Solutions?

Lead and kids Fetal alcohol syndrome Nuclear disarmament Bioterrorism Ocean Fisheries Persistent chemicals The Commons


"Biology combined with diverse humanistic knowledge forging a

science that sets a system of medical and environmental

priorities for acceptable survival.“Global Bioethics (1988)

Bioethics

-------- 1911 - 2001 --------

Van Rensselaer Potter


1860’s - Scientific method in medicine, Gregor Mendel

1928 - Penicillin discovered – widely used WWII

1920’s - Lead in gasoline, lead in paint

1931 - 30 states had sterilization laws on books

1932 - Tuskegee syphilis study initiated

1947 - Nuremberg - The Doctors Trial

1952 - First open heart surgery & Chlorpromazine

1953 - Structure of DNA – Watson & Crick

Ethics and Science


60’s - Thalidomide, mercury, chronic hemodialysis, amniocentesis, informed consent, IRB’s

70’s - Hastings Center founded, bioethics defined, Tuskegee noticed, Belmont Report (3 principles), Genentech Inc. founded, awareness of FAS, sensitivity of developing CNS

80’s - Recombinant microorganism could be patented, lead is harmful to developing brain

90’s - molecular biology, sequencing of human genome (other species), Jurassic Park

00’s - US stem cell research restricted

03 - Human cloned?

Ethics and Science


Question??

Who were the most influential people of the past century?

James Watson (L) and Francis Crick (R), and the model they built of the structure of DNA (and Rosalind Franklin).


ELSI

Ethical Legal / Regulatory Social Implications or Issues What is unsaid or missing? Science Values Politics


Contents

Why this is topic important DNA to RNA to Proteins Stem Cells Cloning – Therapeutic and Human


Stem Cell History

1998 - Researchers first extract stem cells from human embryos

1999 - First Successful human transplant of insulin-making cells from cadavers

2001 - President Bush restricts federal funding for embryonic stem-cell research

2002 - Juvenile Diabetes Research Foundation International creates $20 million fund-raising effort to support stem-cell research

2003?? - California ok stem cell research

2004 - Harvard researchers grow stem cells from embryos using private funding

2004 - Ballot measure for $3 Billion bond for stem cells


Importance

Disease• Diabetes, Spinal

cord injury, Parkinson’s disease, heart disease

Genetic based Disease

• Cystic fibrosis, Huntington’s


DNA – T-A C-G

Thymine (T) Adenine (A)Cytosine (C) Guanine (G)

Over 3 billion base pairs, 30,000 genesHumans are over 99.9% identical


Central Dogma of Molecular Biology

DNA

RNA

Protein

Transcription

Translation


RNA Transcription Protein Translation

DNA RNA Protein

Gene Expression


Human Variability in DNA

• SNPs (single nucleotide polymorphisms)• Many examples directly cause disease

– Huntington’s, Cystic Fibrosis, Muscular Dystrophy, etc.

• The ‘environment’ also plays a big role


...AUC AUC UUU GGU...

...Ile Ile Phe Gly...

...AUC AU- --U GGU...

...Ile Il e Gly...

Normal

CF

Common Cystic Fibrosis Mutation


Parents to Children

Mother & Father both CarriersChildren?

1 – Not a carrier (25%)2 – Carrier (50%)1 – With CF (25%)


Gene Environment Interactions

• PKU and consumption of phenylalanine

• Malaria and Sickle Cell gene

• HIV infection and CCR5 receptor variant

• Alcohol intolerance and aldehyde dehydrogenase

• Beryllium disease (exposure to beryllium)


Sexual Reproduction

The Association of Reproductive Health Professionals


Stem Cell Differentiation

Princeton University


Stem Cell Cultivation

University of Wisconsin-Madison


Embryonic Stem Cells (ESCs)

August 9, 2001 - President Bush restricted federal funding of human embryonic stem cell research to 70 lines thought to be in existence

Only 11 now available and useable

Many researchers calling for change

Science and Politics of ESCs research


Blastocyst Diagram

Princeton University


Human Clones?

Are there human clones?

Yes – Identical Twins(Time 2.19.01)


Cloning Defined

• What is cloning?• Asexual reproduction

• Examples?• Bacteria, fungus• Plants – cutting – potato• Farm animals


Asexual Reproduction

The Association of Reproductive Health Professionals


Cloning Dolly

1997 - 2003

(Roslin Institute http://www.roslin.ac.uk/library/)


Cloning A Sheep



Human Stem Cell Production


Removing Nucleus

Removing the maternal nucleus before nuclear transfer



Nuclear transfer

Nuclear transfer embryo about to be activated



Coning for use in Stem Cells

Cloning techniques for creating stem cells

Therapeutic cloning

Reproductive cloning


IVF – In Vitro Fertilization

Available since 1986 About 100,000 IVF kids in U.S. Often creates extra embryos U.S. - About 400,000 frozen

embryos (unregulated) England – 52,000 (regulated by

government)


Stem Cells and Cloning

Questions or Comments?

bioethics, stem cells & cloning

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