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Stem CellsWhat are the ethical problems facing stem cell technology? State of stem cell legislation in New Zealand and around the world IntroductionStem cells are cells in the human body that have the ability to continuously divide and develop into different kinds of tissues. It is anticipated that in the near future it will possible to trigger stem cells to transform into specific cell types, for example blood, skin and brain cells. These cells could then be able to be used to repair diseased or damaged tissue in patients and may be able to treat diseases such as cancers, spinal cord injury, heart disease and neurological disease. Research using stem cells is a relatively new area. What are stem cells?Stem cells are a type of cell that can generate different kinds of cells. When a normal body cell divides, it creates a copy of itself (for example, a single skin cell will divide into two skin cells). Stem cells, however, can become any type of body cell, including skin cells, blood cells, or muscle cells, depending on the part of the body in which they are located. What are the sources of stem cells?Stem cells can be obtained from a number of sources:
There is debate among the scientific community about the best source of stem cells. Stem cells derived from human embryos are the easiest to isolate and manipulate. Also, embryonic stem cells are totipotent, which means they can create any type of human cell. Stem cells have been found in many tissues of the adult human body, but adult stem cells are more difficult to isolate in tissue and create more limited types of cell. Nonetheless, much research involving adult stem cells is currently being conducted. Stem cells and stem cell linesWhen embryonic stem cells are isolated from the embryo, they can replicate indefinitely. This collection of cells is known as a stem cell line. Stem cell lines are important to researchers as a source of stem cells for experiments, and as common ground for comparison with other research. There is debate about the ethics of creating embryonic stem cell lines, because they involve the destruction of a human embryo. Why are stem cells important?Stem cells are important because they have the potential to be used to repair diseased organs, such as the pancreas in diabetes sufferers, brain cells in sufferers of Parkinson's disease, or damaged spinal nerve tissue, allowing paralysed patients to walk again. The application of stem cells might even be able to slow or stop the ageing process. Figure 1 illustrates the process used to derive stem cells, and their use in medical treatments:
What is the current state of stem cell research?Scientific knowledge about stem cells, as well as the underlying technology is steadily improving. In limited circumstances, stem cell treatments have been successful in humans; however the majority of experimentation is currently being performed in animals. In New Zealand, Professor Richard Faull and Bronwen Connor of Auckland University are conducting research on adult stem cells and brain injury and disease. To date no research using embryonic stem cells has taken place in New Zealand but the Ministry of Health is proposing guidelines to allow scientists to import embryonic stem cell lines from overseas. (The Bioethics Council have published Comments to the Ministry of Health on the “Guidelines on Using Cells from Established Human Embryonic Stem Cell Lines for Research” in response to this proposal, and also Attitudes to Embryonic Stem Cell Research in New Zealand, examining current public awareness of and attitudes to stem cell technology.) The use of embryos in New Zealand for research is likely to be the subject of guidelines produced by the Advisory Committee on Assisted Reproductive Technology. What are the ethical problems facing stem cell technology?Stem cell technology presents a number of ethical issues, including some related to the use of Human embryos for research. The ethics of using stem cells derived from human embryos and foetusesHuman stem cell research relies largely on embryos remaining at the conclusion of in vitro fertilisation procedures. Some see the use of these embryos as acceptable since the benefits are potentially large, and the embryos are otherwise wasted. Others believe that human life begins with conception and that an embryo is a human being and should not be experimented upon or be destroyed by research procedures. Tissue used for stem cell research can also be obtained from aborted foetuses. Abortion is a very contentious issue globally, and many do not consider medical practices derived from aborted foetuses to be ethical. To date only a limited number of foetuses have been used for stem cell experimentation. Therapeutic cloning for stem cell treatmentsA further issue is the potential for the use of 'therapeutic' cloning techniques. This involves creating a cloned embryo with the same nuclear DNA as the patient. The cloned embryo is used as a source of stem cells, which are less likely to be rejected by the patient's body as they have the same DNA. As yet these techniques have not been perfected, but they may well be realised in the future. Therapeutic cloning is not as controversial as reproductive cloning (cloning to produce a new human being), but therapeutic cloning does involve the creation of a cloned embryo, and its destruction to produce stem cells. This manipulation and destruction makes therapeutic cloning a contentious issue for some people. An alternative view is that the embryo would have been otherwise wasted, and that the use of surplus embryos for such a process is ethically consistent. State of stem cell legislation in New Zealand and around the worldIntroductionMany countries around the world have introduced and passed legislation to regulate or even ban stem cell research. This legislation largely focuses on embryonic stem cell research. New ZealandThe Medicines Act 1981 regulates medical research, including stem cell research or medicine in New Zealand. Any potential stem cell trials would be reviewed by the Standing Committee on Therapeutic Trials (SCOTT). The Human Assisted Reproductive Technology (HART) Act 2004 bans reproductive cloning of humans (ie production of a human) but not therapeutic cloning (ie using cloning to produce stem cells). The HART Act also bans genetic modification of gametes and embryos for reproductive purposes, and the use of gametes from foetuses for reproductive purposes. Selection of an embryo on the basis of sex is only permitted where it is to prevent or treat a genetic disorder or disease. Selection of an embryo on the basis of its sex for other purposes is not allowed. Ethical oversight under the HART Act includes a Ministerial advisory committee (ACART) and an ethics committee (ECART). The Advisory Committee on Assisted Reproductive Technology (ACART)provides advice on assisted reproductive procedures and human reproductive research to the Minister of Health, issues guidelines to the ethics committee, and monitors developments in assisted reproductive procedures and human reproductive research. The advisory committee is required to consult on the guidelines that it proposes to issue. The Ethics Committee on Assisted Reproductive Technology (ECART) considers applications for non-established procedures or human reproductive research in line with the guidelines and advice issued by the advisory committee. The ethics committee is able to cancel previous approvals when it becomes aware of serious risk to human health and safety. Those people carrying out research must provide progress reports to the ethics committee and a final report upon completion of the research. Once stem cells are produced, other pieces of legislation may come into play depending on how the cells are to be used. It is anticipated that any early clinical applications of stem cells will require genetic modification of the cells to track them in the body and destroy them should there be undesired effects. The provisions of the Hazardous Substances and New Organisms Act would apply if the technique involves genetic modification of the cells and the Medicines Act would apply if the stem cells were to be used for therapeutic purposes on a person. The Human Tissue Act 1964 is likely to be replaced in 2006. The new legislation will cover the use of human tissue in research, including the issues of consent, safety, storage and disposal. Human embryonic stem cells are human tissue. See also:
AustraliaAustralia passed the Research Involving Embryos Act in 2002. Research may be carried out on any embryonic stem cell line derived from a surplus in vitro fertilisation embryo. Both therapeutic and reproductive cloning are banned under the Prohibition of Human Cloning Act 2002 . In 2005 the Australian government established the Lockhart Committee to review these statutes. United KingdomIn the UK , procedures involving excess human embryos created for IVF procedures are regulated by the Human Fertilisation and Embryology Act 1990. All research involving human embryos is monitored by the Human Fertilisation and Embryology Authority. Therapeutic cloning is permitted under certain conditions. CanadaCanada passed legislation allowing and regulating embryonic stem cell research in March 2004. United StatesIn 2001 President Bush denied federal funding for stem cell research except for existing stem cell lines prior to 2001. Privately funded stem cell research is permissible, but the federal ban has stifled stem cell research in the US . Individual states have the authority to pass laws to permit human embryonic stem cell research using state funds. Unless Congress passes a law that bans it, states may pay for research using human embryonic stem cell lines that are not eligible for federal funding. The state of California passed an Act in 2002 to encourage stem cell research. The state of New Jersey passed a similar act in January 2004. United NationsOn the 8 th March 2005 The General Assembly adopted the United Nations Declaration on Human Cloning, by which Member States were called on to adopt all measures necessary to prohibit all forms of human cloning in as much as they are incompatible with human dignity and the protection of human life. By further terms of the Declaration, Member States were also called on to adequately protect human life in the application of life sciences; to prohibit the application of genetic engineering techniques that may be contrary to human dignity; to prevent the exploitation of women in the application of life sciences; and to adopt and implement national legislation in that connection. The Declaration is a non-binding political statement, which would not prevent States from deciding to permit therapeutic cloning. The European UnionThe European Union's member states are culturally and ethically divided over whether embryonic stem cell research should be performed. However, in late 2003 the European Parliament voted to allow EU research funding grants to embryonic stem cell research projects. More informationIf you want to learn more about stem cells, you can visit the following resources:
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