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Published byNorman George Modified over 9 years ago
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Stem cells through the lens of the Korean cloning scandal
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A lens through which to view general issues of stem cell research Promise of embryonic stem cells to cure disease and as a driver of a medical industry Ethical pitfalls Difficulty of the technique Policy implications for Australia
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Skin cell, limited proliferation Skin stem cell (adult stem cells), proliferates but only makes skin cells Stem cells 101 Embryonic stem cells proliferate indefinitely and make all tissues BIOLOGICAL GOLD!!!!
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Making embryonic stem cells
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BUT SOME TISSUES ARE MORE DIFFICULT THAN OTHERS MOST DIFFICULT DONE
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A LONG WAY TO GO TRAIN CELLS TO MAKE SPECIFIC TISSUES ELIMINATE CANCER CELLS GRAFT REJECTION??? THERAPEUTIC CLONING PROVIDES MATCHED TISSUES, HENCE THE GREAT PROMISE
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Cattle cloning: about 10% success rate
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In Feb 2004, Hwang announces first success But it was a very qualified success: 1.Couldn't prove it was a clone 2.Only cumulus cell 3.Only if from same egg and nucleus donor? 4.242 eggs! Cumulus cell
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Woo Suk Hwang’s group dazzle the world May 2005: it’s a go-er! -Cloned from skin cells of men, women and children -increased success rate over 10 fold (17 eggs per cell line), practiced with cow eggs!
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Astonishing that no-one suspected Korean work ethic 24/7 Supportive policy and funding Technical prowess borne of lifetime’s use of steel chopsticks
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Scientific smoking guns Proofs that they were embryonic stem cells: visual appearance, marker proteins, teratomas
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Marker proteins look good
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Teratomas for three of the cell lines
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Spot the duplication?
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Are they cloned stem cells? Compare DNA fingerprints of donor skin cells and stem cell lines
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DNA Fingerprints
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Policy implications Women were exploited (suffered side- effects; some did it for money) Scientists behaved dishonestly (now also an issue of missing millions) Ban the technique?
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Legislation that permits advance while preventing transgressions TC will not be used to produce customized tissues—its too hard For model diseases its still a worthy goal
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One in 8000 births, biggest genetic killer of kids under 2 yo Disease causes death of motor neurons Use Therapeutic cloning to make cell lines for screening drugs Spinal Muscular Atrophy-a case in point
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Put cloned cells to work tomorrow Many diseases a mystery: genes and environment ALS: 95% out of the blue, MN die off No real animal models Cloned cells from patients could be first real models to study the disease ES cells (not adult stem cells) can be made into Motor Neurons (H. Wychterle 2002, Cell) Test 100,000 compounds a day on these model patients
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Unscientific debate “Pick and choose” notions of research are misguided Furfies — adult stem cells have more runs on the board. Only in bone marrow transplants and skin grafts Novel applications remain unproven and highly contentious. Common sense: in exploration success comes from following as many paths as possible
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