Frequently Asked Questions Michigan Law and President Obamas Executive Order Embryonic, Adult, and IPS (induced Pluripotent) Stem Cells Benefits of Stem Cell Research Embryo and Fetus Definitions Cloning Public Opinions Ethics Federally Approved Stem Cell Lines Stem Cells: Myth Vs. Fact

On Nov. 4, 2008, Michigan voters approved Proposal 2 by a margin of 53 percent to 47 percent. The ballot measure amended the state constitution, overturning a 1978 Michigan law that prohibited the use of human embryos for research, even if those embryos were to be discarded.

The law change enables Michigan researchers to derive new embryonic stem lines, using procedures already employed in laboratories around the world. The new state law allows the use of human embryos for research that is already permitted under federal law, provided that the embryos:

The new law makes Michigan one of just three states that protect stem cell research in the state constitution, while also enshrining specific restrictions. In addition to the restrictions listed above, the new law prohibits the buying or selling of embryos, as well as removing stem cells from embryos more than 14 days after cell division begins. It also requires the informed, written consent of embryo donors.

Michigans ban on human cloning was not altered by Proposal 2 and remains in full effect.

All human embryonic stem cell research at the University of Michigan will fully conform to the provisions of the new state constitutional amendment. In addition, U-M scientists will strictly adhere to the guidelines for the conduct of human embryonic stem cell research issued by the International Society for Stem Cell Research.

All stem cell research involving human subjects, including research in which embryos are donated for the derivation of stem cell lines, must be reviewed and approved by the University of Michigans Institutional Review Board. The board is a committee of ethicists, physicians, scientists and attorneys who review all aspects of the proposed research to ensure that is beneficial and ethically conducted.

All stem cell research must also be reviewed by the U-M Pluripotent Stem Cell Research Oversight Committee to independently ensure that all stem cell research projects are performed ethically.

On March 9, 2009, President Obama signed an executive order lifting the Bush administrations strict limits on federal funding for embryonic stem cell research. As a result, the federal government is expected to invest millions of dollars in new embryonic stem cell research.

The presidents action holds special significance for University of Michigan researchers. The passage of Proposal 2 means that U-M scientists can now compete for the new funding: Millions of dollars in new federal research funds could flow to the University of Michigan.

These two landmark changes the passage of Proposal 2 and the presidents executive order will allow world-class scientists in Michigan to devote their full talents to the search for new cures.

Embryonic stem cells exist only at the earliest stages of embryonic development and are capable of making any cell type in the body. Under the right conditions, these cells retain the ability to divide and make copies of themselves indefinitely. Scientists are beginning to understand how to make these cells develop into any of the more than 200 different types of cells in the human body.

A. Adult stem cells, also known as tissue-specific stem cells, are present in adults, children, newborn infants and developing fetuses. Adult stem cells are more limited and specialized than embryonic stem cells. They have the ability to make just one or two kinds of tissue, such as blood and immune system cells, brain or muscle cells. Adult stem cells also have a more limited capacity to replace themselves than do embryonic stem cells.

iPS cells are adult cells reprogrammed to behave like embryonic stem cells. While iPS cells are an exciting discovery, these cells could never be used in patients because the use of viruses to reprogram these adult cells predisposes the cells to cancer. As a result, these cells cannot replace the use of embryonic stem cells. There is widespread agreement among leading stem cell researchers, including the scientists that developed iPS cells, that research must continue on all types of stem cells including those derived from embryos.

Some of the work announced in November 2007 was done at the University of Wisconsin by James Thomson. Early stages of this work used embryonic stem cells derived from leftover in vitro fertilization (IVF) embryos. This work would have been illegal in Michigan, illustrating how restrictions under Michigan state law stifle discovery and impair Michigan scientists ability to participate in critical research.

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Research with embryonic stem cells may lead to new, more effective treatments for serious human ailments and alleviate the suffering of thousands of people. Diseases such as juvenile diabetes, Parkinsons disease, heart failure and spinal cord injuries are examples.

Bone marrow transplants have been performed for decades and involve the infusion of adult stem cells. Research based on embryonic and adult stem cells has yielded promising results for the treatment of Parkinsons disease and diabetes Stem cell research also has generated new knowledge about basic cell mechanisms that is critical to understanding the causes of disease, such as cancer.

Some have criticized embryonic stem cell research by arguing that adult stem cells have delivered more treatments, but that observation is misleading. While adult stem cells have been studied for decades, human embryonic stem cells were first isolated in 1998. There has not yet been time to develop new therapies using embryonic stem cells.

The overwhelming majority of stem cell scientists believe that to make the most rapid progress against disease, researchers must use all the weapons in their arsenal. That means using both embryonic and adult stem cells.

We cant say how long it will take to find new treatments for any specific disease using embryonic stem cells. Biomedical research typically has a time frame of 10, 20, even 30 years. Fourteen years elapsed between the first unsuccessful clinical trial of bone marrow transplantation and the first successful transplant among unrelated patients. Now bone marrow transplants are widely touted as the best example of a successful stem cell therapy.

Biomedical research takes a long time, but the sooner the research starts, the sooner it will yield new insights and new treatments. If research were stopped by uncertainty, we never would have developed blood transfusions, cardiac bypass surgery, insulin therapy for diabetes, kidney dialysis, antibiotics, organ transplants and many other treatments we now take for granted.

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The embryos used for stem cell research are about the size of the period at the end of this sentence. They are derived from four- and five-day-old embryos created through in vitro fertilization. Embryos at this stage, called blastocysts, are spheres containing about 100 cells. They have no nervous system, no heart, and no specialized tissues. Many of the cells are still undifferentiated, meaning they can become any type of cell in the human body.

An embryo becomes a fetus about eight weeks into gestation, when specific tissues and organs have started to form.

Thousands of embryos that cannot be used for fertility treatment are discarded as medical waste each year by IVF clinics. Embryos are discarded for a variety of reasons. Some do not develop normally, while others are found to carry genetic defects that cause serious disease. Some parents simply choose to discard leftover embryos when they are done with fertility treatment. With the parents consent, embryos slated for disposal can be used by researchers to derive embryonic stem cells.

Yes. Parents can elect to donate unused embryos to others seeking fertility treatment, a practice sometimes called embryo adoption. But few parents choose to do so. For every embryo that is donated to others, more than 100 embryos are discarded. Currently, more than 400,000 embryos are frozen in fertility clinics, and most will eventually be discarded.

At the same time, fewer than 200 children have been born through the Snowflakes Embryo Adoption Program since it was founded in 1997. There is no conflict between embryo adoption and stem cell research, as it is up to parents to decide whether to donate their unused embryos to others, to discard the embryos, or to donate them for medical research.

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When discussing stem cells and cloning, it is important to distinguish between reproductive cloning and what scientists call therapeutic cloning.

Its a laboratory technique that uses somatic cell nuclear transfer (SCNT) to make embryonic stem cell lines. In SCNT, the nucleus of an unfertilized donor egg is extracted and replaced with the nucleus from an adult cell, such as a skin cell. Given the proper signals, the egg can be tricked into repeatedly dividing. The resulting nuclear transfer product is allowed to develop for several days. Then some of the cells are removed and placed in a laboratory culture dish, where they grow into an embryonic stem cell line that can be used for research.

So far, this procedure has been accomplished in animals but not in humans.

In reproductive cloning, SCNT is used to create a nuclear transfer product that is then implanted into a uterus to generate a pregnancy. These nuclear transfer products rarely develop normally and are rarely able to establish a pregnancy. Nonetheless, this is the process used to create Dolly the famous cloned sheep after hundreds of unsuccessful attempts. A human being has never been cloned, and it is the overwhelming consensus among U.S. scientists that human reproductive cloning should be banned.

Animal-cloning experiments demonstrate that reproductive cloning is unsafe: Pregnancies are rare, and when they do occur they often produce abnormal or unhealthy offspring. Most scientists believe that implanting an SCNT-derived product into a womans uterus should be illegal.

Until recently, nuclear transfer or therapeutic cloning was the only way that scientists imagined it would be possible to derive patient-specific cell lines. But in the past year, it became possible to derive patient-specific pluripotent lines by reprogramming adult human cells, making so-called iPS cells. Given this change in the scientific landscape, and given that it has never been possible to do nuclear transfer successfully with human eggs, nobody in Michigan wants to pursue cloning. Nonetheless, iPS cells cannot replace the derivation of ES cells because iPS cells could never be used in patients due to their predisposition to cancer.

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Most Americans, regardless of their religious or political affiliation, support embryonic stem cell research. A 2007 study published in Science surveyed infertility patients who had embryos stored at fertility clinics. The study found 60 percent of the patients expressed willingness to donate embryos for stem cell research, compared to 28 percent who were willing to donate unused embryos to other patients seeking fertility treatment.

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We respect the values of people who hold this view. However, most Americans believe this research can be conducted ethically. Many see it as a pro-life position because this research has the potential to alleviate the suffering of thousands of people.

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U.S. scientists can use federal funding only for research using government-approved embryonic stem cell lines, which were created on or before August 9, 2001. But most of those lines, it was later determined, do not contain viable embryonic stem cells. And all of them are contaminated with animal products. In addition, the approved lines dont carry the genetic defects that make it possible to model inherited human diseases.

Furthermore, it has recently been discovered that many of these embryonic stem cell lines dont come close to mirroring the diversity thats present in American society or in Michigan country.

By growing embryonic stem cells that carry disease-causing genetic defects, scientists hope to learn what goes wrong inside cells and to test new drug candidates to combat those diseases. Many believe this approach offers the best hope for treating diseases like Alzheimers.

One of the fundamental principles of clinical trials is that we test new medicines in a diverse patient population that mirrors the diversity that is present in our society. For example, if we only test new medicines on white males, there would be a risk that we would only develop medicines that work for white males.

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Myth Adult stem cells are as useful as embryonic stem cells.

Fact Embryonic stem cells have the ability to create any cell type in the human body. Adult stem cells are more specialized; they generally make cells only from their tissue of origin. Thus, embryonic stem cells can do things that adult stem cells cannot do. To maximize the chances of discovering new cures, it is essential to pursue research on both embryonic and adult stem cells.

Myth We dont need embryonic stem cell research because of the recent breakthrough enabling scientists to reprogram human skin cells into cells that behave like embryonic stem cells.

Fact Scientists agree it is too early to assess the techniques full potential and determine whether the reprogrammed cells are functionally equivalent to embryonic stem cells. In addition, the technique can cause mutations that predispose cells to cancer. As a result, some scientists are concerned that the reprogrammed cells will never be suitable for use in patients. For the foreseeable future, stem cell researchers agree that research should continue along all avenues, using embryonic stem cells, adult stem cells, and reprogrammed cells.

Myth Adult stem cells have been proven effective in treating more than 70 diseases.

Fact While adult stem cell research holds much promise, blood stem cells offer the only proven adult stem cells therapies. The claim that adult stem cells have been used to cure more than 70 diseases has been widely discredited.

Myth Stem cells from amniotic fluid and umbilical cord blood can be used instead of embryonic stem cells.

Fact Amniotic fluid and umbilical cord blood contain adult stem cells. They hold promise for therapy but do not have the properties or potential of embryonic stem cells.

Myth The stem cell lines approved by the federal government provide an adequate source of embryonic stem cells for research.

Fact The approved stem cell lines were created on or before Aug. 9, 2001. Scientists later determined that those lines are contaminated with animal proteins. In addition, none of the approved lines was created to model human disease. Although President Bush initially intended to make more than 70 federally approved lines available to scientists, most of these lines turned out to be inadequately characterized, and only 16 such lines remain. Furthermore, many of these lines come from a single clinic in Israel, thus they do not mirror the ethnic and racial diversity in American society.

Myth Religious people oppose embryonic stem cell research.

Fact Some religious people are in opposition. Others believe that embryonic stem cell research is pro-life and that it is immoral not to pursue this research, because of its potential to reduce human suffering. Most religious traditions, including Judaism, Hinduism, Islam, Buddhism, and some branches of Christianity do not consider embryonic stem cell research to be immoral.

Myth Embryonic stem cell research uses embryos that have begun to develop as babies.

Fact Stem cells are derived from blastocysts that have only developed for about five days after fertilization. The blastocysts used for this research develop entirely in laboratory dishes in fertility clinics and are never implanted in a womans uterus. These early stage embryos consist of about 100 cells and are the size of the period at the end of this sentence. At this stage, the cells are undifferentiated: They have no nervous system, no heart, no limbs and no specialized human tissues.

Myth Embryonic stem cell research uses aborted fetuses.

Fact There is no connection between abortion and human embryonic stem cells. By the time a human embryo has implanted in the uterus, its cells have specialized to the point where they can no longer be used for the derivation of embryonic stem cell lines.

The embryos used to derive stem cells are created in dishes in fertility clinics. They are never transferred into the human body and are donated for medical research only when parents decide they are no longer needed for fertility treatment.

Myth Embryos discarded by fertility clinics could be donated to another family rather than discarded or used for research.

Fact Snowflake Children is a term used to describe some babies born from leftover IVF clinic embryos donated to other infertility patients. But the Snowflakes Frozen Embryo Adoption Program claims fewer than 200 births since it began in 1997. Meanwhile, thousands of leftover embryos are discarded each year and more than 400,000 embryos are currently frozen in fertility clinics; most will eventually be discarded.

Many embryos created for IVF are discarded because they do not develop normally or are known to carry serious genetic abnormalities. Such embryos are not suitable for implantation. But in the laboratory, these defective embryos could help researchers understand genetically linked diseases and develop treatments for them.

MythStem cell research is unregulated and unrestricted, thus paving the way for scientists to go down a dangerous path.

FactThis research is extensively regulated under federal laws (National Institutes of Health, Food and Drug Administration, Institutional Review Boards, and more), and guidelines from the National Academies and the International Society for Stem Cell Research. There are additional restrictions being introduced in a Michigan ballot proposal. For example, under this ballot proposal, embryos could not be bought or sold, could only be generated for the purpose of fertility treatment, and then could only be used for stem cell research if they could no longer be used for fertility treatment and were donated with the informed consent of the donor.

Excerpt from:

University of Michigan Stem Cell Research | Frequently ...

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