UK euthanasia: Two of the UK's royal medical colleges have dropped their opposition to a bill which would allow doctors to assist patients to commit suicide. The Royal College of Physicians and the Royal College of General Practitioners have both adopted a neutral stance on a controversial private members' bill. The British Medical Association remains opposed.

A year after debate in the United Nations' legal committee over an international ban on cloning ended in stalemate, the UN is again trying again to thrash out an agreement. The delegates are deeply divided, with about 60 countries led by Costa Rica opposing the creation of human embryos for research and 20 countries led by Belgium supporting it. There is unanimous support for a ban on reproductive cloning. The debate is expected to last for two days. Secretary General Kofi Annan has expressed his personal support for therapeutic cloning, but insists that "it's an issue for the member states to decide".

It is difficult to predict the outcome of this week's deliberations. A decision could be deferred or the two sides could abandon the idea of a consensus, leaving countries free to regulate human cloning themselves without reference to an international covenant. In any case, it is unlikely that countries like Britain, China, South Korea, Japan, Finland and the Netherlands, which currently allow regulated therapeutic cloning, would sign a treaty which banned it.

Democratic presidential nominee John Kerry continued to boost stem cell research in the closing days of his campaign, painting his opponent as an enemy of science and progress. In Ohio he jeered that if George Bush had been President during other periods in American history, he would have sided with the candle lobby against electricity, the buggy-makers against cars, and typewriter companies against computers."

Armed with a warm endorsement from the widow of Christopher Reeve, the recently deceased quadriplegic activist for stem cell research, Mr Kerry promised that he would remove restrictions on scientific research. "It is wrong to tell scientists that they can't cross the frontiers of new knowledge," he declared. "It is wrong morally and it is wrong economically. When I am president, we will change this policy, and we will lead the world in stem cell research."

However, his running mate, John Edwards, blew one breath too many into the balloon of stem cell hype earlier this month. Edwards told a rally in Iowa, "If we do the work that we can do in the country, the work that we will do when John Kerry is president, people like Christopher Reeve are going to walk, get up out of that wheelchair and walk again".

Edwards's opponents pounced on his tub-thumping rhetoric and tore it to shreds. In a scathing column in the Washington Post, conservative political pundit Charles Krauthammer declared that "in my 25 years in Washington, I have never seen a more loathsome display of demagoguery. Hope is good. False hope is bad. Deliberately, for personal gain, raising false hope in the catastrophically afflicted is despicable." Krauthammer, who is a psychiatrist and a paraplegic, has been one of the leading sceptics in the American media about the potential of stem cells. He is also a member of the President's Council on Bioethics.

However, this did not stop other prominent politicians from endorsing embryonic stem cell research. Former vice-president Al Gore argued in Seattle that researchers should not be hindered from pursuing opportunities to save lives. And in California, Governor Arnold Schwarzenegger endorsed a controversial US$3 billion bond issue which would pay for embryonic and adult stem cell research.

An MIT biotechnologist has pleaded with Harvard University not to pursue plans to do therapeutic cloning. Associate Professor James Sherley wrote in the Boston Globe that "adult stem cell research is predicted to beat the pants off human therapeutic cloning research when it come to yielding significant advances in cell medicine." Given the unresolved debate over whether the research is ethical, he argues, "no reviewing body could, in good faith, approve it". Prof Sherley also argued that the moral argument for therapeutic cloning was self-contradictory. At least reproductive cloning (which he staunchly opposes) creates life, while therapeutic cloning destroys it.

In a radical break with accepted methods of organ donation, a Colorado executive has found a new kidney after linking up with a living American donor on a private website in Boston. Bob Hickey found his donor, Rob Smitty, of Tennessee, through matchingdonors.com, an internet site which charges US$295 a month to post patients' stories. The hospital where the procedure was done asked both men to sign statements that the donor was not profiting from the procedure, as US law forbids selling body parts. Hickey says that he is not paying for the kidney, but will reimburse Smitty about US$4,500 for his expenses.

The private agency which manages American organ supplies, the United Network for Organ Sharing, has criticised the website for undermining a system which promises a fair distribution of organs based on who is sickest and who has waited the longest for a transplant. Living organ donors are normally relatives or close friends, but the website brings together total strangers, short circuiting the long waiting list.

Mr Hickey had been on dialysis for five years and had nearly given up hope of finding a donor. Then he discovered the website. In response to his internet plea, he quickly received 500 serious queries, including 50 who matched his body and blood type.

According to the Boston Globe, "MatchingDonors.com touches on two of the most sensitive issues in the field of organ transplantation: the use of money to encourage organ donations and the wisdom of encouraging healthy people to risk their health to donate organs to people other than immediate family members. Medical ethicists fear that encouraging people to donate organs to strangers increases the risk of payoffs for organs or the exploitation of donors who are not psychologically stable."

The World Medical Association has announced that it will amend its policy on how doctors should behave in times of armed conflict to emphasis that the ethical standards which they observe in times of peace do not change because of war. This is intended to help doctors behave in an ethical way when they are caught between cooperating with the police or the army and their duty of care to their patients.

The WMA reaffirmed its policy that it is "unethical for physicians to give advice or perform procedures that are not justifiable for the patient's health care or that weaken the physical or mental strength of a human being without therapeutic justification."

A small number of people in the deaf community would use prenatal genetic testing or pre-implantation genetic diagnosis to ensure that they have a deaf child, according to a news feature in Nature. Although the notion might horrify the non-hearing-impaired, many deaf people view their condition not as a handicap, but as a rich and vibrant culture. Some might fear that they could not share this way of life with a hearing child.

A British genetics counsellor, Anna Middleton, has studied attitudes of deaf people to prenatal testing. Although her results were inconclusive, she did find that a few deaf people would consider aborting a child if it could hear. Geneticists are also becoming more willing to help deaf people make such a reproductive choice. According to a survey, more than a third of geneticists in the US, Italy, Russia, Cuba and Israel would assist a deaf couple perform the necessary tests, although the figure in Norway was just 1%.

In the absence of a law governing stem cell research, the US National Academies are studying guidelines on the production of chimaeric embryos, which mix cells and DNA from different species. Many researchers believe that they could learn valuable lessons about human development by injecting human embryonic stem cells into embryos, foetuses or newborn animals of other species.

For instance, Irving Weissman, of Stanford University, one of the leading figures in US stem cell research, feels that much of his own work is only be possible with human-mouse chimaeras. It would even be possible to construct a mouse whose entire brain would be made of human-derived cells, says Weissman, although this is not an experiment which he has performed. Although Weissman agrees that there should be some limits on research, he told Nature that "I haven't heard the reason yet for restricting certain experiments." He thinks that the "yuck factor" is no reason to ban an experiment.

After a two-day meeting earlier this month the academies plan to issue guidelines in February about chimaeras and other contentious issues in stem cell biology. These will not have the force of law, but the International Society for Stem Cell Research will recommend that its members observe them.

UK doctors say that a six-year-old boy has been cured of a rare blood disorder because of transplants from a baby brother who was created to give him tissue-matched healthy blood cells. Charlie Whitaker was born with Diamond Blackfan anaemia, which is normally a fatal condition. His parents failed to get permission from British authorities to create a "saviour sibling", so they sought help from a Chicago clinic which offered pre-implantation genetic diagnosis. A baby brother was born last year.

Ethicist John Harris, of the University of Manchester, denied that Charlie's case was a step towards designer babies or creating babies for spare parts. "What better reason could there conceivably be for having a child than to save the life of an existing person? There is no better reason," he declared. Opponents of the treatment countered that "you are using that child as a means to an end, rather than as an end in itself," in the words of Dr David King, of Human Genetics Alert.

Voters in Switzerland will decide in a referendum next month whether scientists should be allowed to extract stem cells from surplus" IVF embryos. A law to this effect was passed last year by the Swiss parliament. However, green and anti-abortion groups joined forces and collected enough signatures to force a referendum on the issue. The government and science organisations are campaigning to support a Yes vote. At the moment, only one scientist is doing research with human embryonic stem cells in Switzerland, but she imports her cells. Anita Holler, of the Swiss Federal Office of Public Health, says that "many researchers using adult stem cells say they are waiting until the new law is passed to work with embryonic stem cells."