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Quotation of the Day. “The Ramones don’t jam.” — Jerry Harrison. About our schedule MARCH 21: NO CLASS MARCH 26: NO CLASS The next time we meet: MARCH 28: QUIZ #4 ON SINGER. CLONING. Cloning!. How babies are made (PG version) Sperm fertilizes ovum.
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Quotation of the Day “The Ramones don’t jam.” — Jerry Harrison
About our schedule MARCH 21: NO CLASS MARCH 26: NO CLASS The next time we meet: MARCH 28: QUIZ #4 ON SINGER
How babies are made (PG version) Sperm fertilizes ovum. This takes place in fallopian tube. Fertilized ovum is a single cell. It divides a few times. The cell-cluster travels down tube, into uterus. The cell-cluster attaches to the uterus wall. Nine months later, a baby is born.
But . . . The process of fertilization and cell-division is very delicate, and things can go wrong. About 40% of the time, the cell-cluster never implants in the uterine wall. It is washed out with the monthly menstrual flow, and the woman never knows that she almost got pregnant.
But . . . • 1 in 12 couples is infertile, and today this is treated as a medical problem. • Treatments include: • scheduled sex • fertility drugs • IVF
Some facts about in vitro fertilization • Current cost: $10,000 per try • Chances of success: 25% • Chances of birth defects: same as in “normal” pregnancy • In U.S., since 1981, about 45,000 children have been born in this way.
Leon Kass President Bush’s Ethics Adviser Pope John Paul II Leading opponents of IVF
Ethical Objections: • It’s unnatural--we are “tampering with sacred things.” • the problem of the discarded embryos • the slippery slope
Cystic Fibrosis • a genetically transmitted disease • 1 in 22 caucasians are carriers • if both parents are carriers, 25% chance the baby will actually have the disease
What can be done? Genetic screening • instead of beginning pregnancy in the “normal” way, use IVF techniques • after fertilization occurs, when zygote is 4-8 cells, see if zygote will have CF • implant only zygotes without CF • so far there have been about 200 successful screenings of this sort
Cloning Somatic Cell Transfer
The Three Most Important Facts About Human Cloning A clone would be a baby just like any other baby. There is no important difference between a clone and an identical twin. You cannot duplicate yourself.
Would cloning be unethical? The most popular arguments: • A clone would not have a soul. • A clone would have no mother or father. • Clones could be used for “spare parts.” • Rich people would want to make copies of themselves. • If we cloned Michael Jordan five times, we would have a hell of a basketball them.
Would cloning serve any good purpose? • A couple has a child, call him Bobby. • Bobby is killed. • They want to have another child, • but the man is sterile. • Bobby’s tissue samples still exist. • They can use SCT techniques to have a child with Bobby’s DNA. • Would this be wrong?
But there’s a good reason why human cloning should not be done at the present time: • Our techniques are not yet good enough to ensure that the baby would be OK.