Tom Douglas

Iterated in vitro reproduction and genetic orphans

In an article soon to be published in the Journal of Medical Ethics, Rob Sparrow imagines a procedure via which multiple generations of human embryos might be created in the laboratory. Egg and sperm cells would first be generated from existing or new human pluripotent stem cell lines. The resulting eggs would be fertilised using the sperm to create zygotes and ultimately embryos. Embryonic stem cells would then be harvested from these embryos and used to create new egg and sperm cells, which would in turn be used to fertilise one another to create further embryos. This process could be iterated, in principle indefinitely.

Let’s call this procedure ‘iterated in vitro reproduction’ (Sparrow calls it ‘in vitro eugenics’). Iterated in vitro reproduction is not yet possible, but, citing recent developments in the science of stem cell-derived gametes, Sparrow argues that it may well become so, though he acknowledges are number of significant hurdles to its development. He also discusses a number of possible applications of the technology and calls for an ethical debate on these. The most controversial application would be in the creation of designer children. Consider the following case, which is a variant on one of the scenarios imagined by Sparrow:

Jack and Jill present to a fertility clinic. Jack provides a sperm sample, and fertility doctors harvest a number of eggs from Jill. These eggs are fertilized with Jack’s sperm to create embryos, from which embryonic stem cells are derived. These stem cells are then induced to develop into eggs or sperm which are used to fertilise one another, and so on. The process is iterated numerous times, and at each stage, the embryos are genetically screened via pre-implantation genetic diagnosis. This screening is used to inform a process of selective crossing, so that, over several generations, the population of embryos evolves towards certain genetic dispositions desired by Jack and Jill (a disposition towards longevity, say). This process is aided by adding small amounts of genetic material from stem cell lines derived from other individuals. Eventually, doctors identify an embryo with almost exactly the desired combination of genes, and this embryo is implanted into Jill’s womb and carried to term. A child, Jarvis, is born.

Cases like this raise numerous ethical issues, some of which are discussed by Sparrow and the seven commentators on his paper. However, they also raise an interesting conceptual question: would the users of such a technology be the genetic parents of the resulting offspring? Would Jack and Jill be the genetic parents of Jarvis?

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Destroying one ecosystem and constructing another: biodiversity offsetting and particular value

Suppose that the government is proposing a new policy regarding buildings of historical significance. Rather than simply banning the destruction of ‘listed’ buildings, the new policy would allow their destruction, provided that whoever destroys the building agrees to construct, somewhere nearby, a new building of a similar size, in a similar style, exhibiting a similar range of architectural innovations, and of a similar level of beauty. Blenheim Palace could be flattened and built over with a shopping mall and carpark, provided that mall developers agreed to construct a replica of the palace somewhere nearby.

Most would be disturbed by such a policy. Part of the reason that they would be disturbed, I presume, is that it seems to manifest a failure to recognise the true value of historical buildings. Not all of the value of historical buildings consists in their possession of generic properties like ‘being beautiful’, ‘being in the baroque style’ or ‘using space to dramatic effect’. Some of their value is value that they have as particular objects, and that could thus not be realised in any other object. Part of the value of Blenheim Palace derives from it’s being the birthplace of Winston Churchill. This value could not be realised in a replica of the palace built 5 miles down the road.

Of course, no-one is proposing a policy of sort I’ve just outlined. I bring it up because I think reflecting on this kind of case may throw some light on recent discussion regarding biodiversity offsetting (see, for example, here, here  and here). Continue reading

Living near a busy road can kill you

Early April saw some unusually smoggy days across much of Western Europe, resulting in widespread media attention to air pollution.
(See, for example, here, here and here.) On one day, air quality in some parts of London was worse than in Beijing. Further attention has been drawn to the issue by a number of recent official reports, including one from the World Health Organisation, which has declared that air pollution is now the world’s biggest single environmental threat to health.

As has been noted, media coverage can give a misleading picture of the health risks of air pollution. Coverage tends to focus on short-term peaks, such as those seen recently in Western Europe, but the health risks of air pollution are primarily related to long term exposure, and show no ’safe threshold’ effect. Elevated baseline levels of pollution are thus more of a problem than occasional peaks.

There’s another important aspect of air pollution that often goes unnoticed; small geographical differences can have a marked effect on exposure to air pollution and thus on risk of adverse health effects. For example, living near a busy road appears to substantially increase air pollution-related mortality. A study published last year in the Lancet (press summary here) investigated the effects of very local differences in air quality on mortality by pooling 22 European cohort studies. The investigators found that an increase in average annual fine particulate (PM2.5) exposure of 5 µg/m3 was associated with a 7% increase in the risk of dying from all natural causes. This is approximately the difference between living on a busy urban road and living in a traffic-free area. The finding was robust in the face of correction for various possible confounding factors. Continue reading

What’s wrong with adopting out an adopted child?

‘Re-homing’ is a term coined to describe the adopting out of adopted children. Reuters today published a long story on the practice, describing several cases in which children adopted from overseas by American parents were then put up for adoption again within the States, in one case only a few days after the initial adoption.

The adoptions described in the Reuters piece are problematic for obvious reasons. It appears that lax oversight arrangements in the US, particularly for intra-state adoptions, have allowed couples to adopt out their children with little or no vetting of the new parents, in some cases into abusive families, and often without much consideration of the child’s interests. But might there also be less obvious considerations in play here? Continue reading

Journal of Medical Ethics special issue on the ethics of stem cell-derived gametes

Recent scientific developments suggest that it may become possible to create viable human gametes from human stem cells. It has been suggested that this will lead to the development of a range of new fertility treatments as well as new strands of research. More speculatively, some have argued that it may

  • Allow the radical enhancement of human reproductive capabilities, for example, by allowing same-sex couples or post-menopausal women to have genetically-related offspring
  • Provide new means of creating ‘designer babies’, for example, by easing constraints on the number of embryos that can be produced in IVF.

In a feature article forthcoming in the Journal of Medical Ethics, Robert Sparrow discusses the possibility that stem cell technologies might be used to facilitate what he calls ‘in vitro eugenics’; the deliberate and selective breeding of multiple generations of human embryos in vitro. The Editors of the Journal of Medical Ethics now invite submissions for a special issue addressing the ethical questions raised by Sparrow’s paper and by stem cell-derived gametes more generally.

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Treating ADHD may reduce criminality

Pharmaceutical treatment of attention deficit-hyperactivity disorder (ADHD) is associated with reduced criminality according to a study published yesterday in the New England Journal of Medicine. The study of over 25,000 Swedish adults with the disorder found that men undergoing pharmaceutical treatments had a 51% chance of committing at least one crime in a 4-year period compared to 63% for those not in treatment. The risk of criminality for women with ADHD was 25% for those taking medication, and 31% for those not in treatment. It’s possible, of course, that the reduction in criminality associated with treatment was due not to the treatment itself, but to other factors, such as desire to improve behaviour, which could have both motivated treatment and reduced criminality. However, even when the investigators adjusted for likely confounders, they found that treatment was associated with significantly reduced criminal offending. Thus, their findings are at least suggestive of a causal relationship between medication and reduced crime.

It will be interesting to see how such a relationship, if it can be further supported, will be viewed by the general public and medical profession. Will it be seen as strengthening or weakening the case for ADHD treatment?

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Hillsborough, Heysel and the Availability Bias

One of my clearest childhood memories is of seeing images  of the 1989 Hillsborough Disaster on the television news. Ninety-six Liverpool fans died in the crush, with an estimated 766 injured. I lived on the other side of the world, had never been to see a football game, and presumably had little comprehension of what the victims had gone through, yet the images of the crush, and of a few people being hauled to safety from it, made a strong and disturbing impression. Continue reading

Animal antibiotics

Suppose that a despotic political regime is keeping its citizens in cramped and unhygenic labour camps. The survival and and economic productivity of the incarcerated individuals is sustained only through the widespread administration of antibiotics which helps to prevent epidemics. It is difficult for international organisations to do anything about these work camps, but one thing they could do is cut off the supply of antibiotics. This would risk the lives of thousands of inmates in the short term, but can also be expected to put an end to the work-camp system in the longer term, since it would render the camps uneconomic.

Should the international organisations cut-off the supply of antibiotics? It is doubtful whether they should.

But now suppose we replace the work-camps with chicken houses and sow stalls, and the citzens with farm animals. Many farm animals held under cramped and unhygenic conditions are kept alive, and economically productive, only through the widespread administration of antibiotics. Restricting access to these antibiotics would force the agricultural industry to reform these practices. In this case it seems more plausible that antibiotic use should be restricted. At least, this is what Robert S. Lawrence writes in The Atlantic.

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Which is least unethical—buying a Mac, or buying a PC?

Recent news stories have brought to public attention the fact that many Apple products, including iPhones, iPads, and Macs, are produced in part in factories with a record of using child labour, failing to provide safe work conditions, and requiring employees to work long shifts for low wages (see, for example, here, here, here and here). This raises the question: should we all stop buying these products?

Suppose you need a new laptop, or at least, are going to buy one. Leaving aside ethical considerations, you are indifferent between getting a Mac and buying a PC laptop from one of Apple’s competitors. Which should you buy?

To answer this, we need to say something more about the situation at factories run by Apple’s Chinese suppliers. Much of the attention has focused on Foxconn, which assembles the iPad and iPhone. It’s alleged that Foxconn negligence was responsible for a blast which killed two people and injured more than a dozen; that it exposes workers to toxic chemicals without adequate protection; that it requires illegal levels of overtime (often more than double the legal limit of 36 hours per month) for which it frequently does not pay in full; that it deceives potential recruits regarding pay rates; that workers are humiliated by supervisors; that workers often have to stand almost uninterrupted for a 12 hour shift; and that poor work conditions contributed to a spate of suicides at the company’s Shenzen plant in 2010. In addition, Mike Daisey, a New York performer who visited the Foxconn plant in Shenzen, reports that he met children in the age range 12-14 who were working in the plant. They told him that it was not difficult for children of their age to find employment there.

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Taking drugs to help others

Primaquine is an anti-malarial drug. When taken as a single dose by someone infected with the falciparum malaria parasite, it reduces the risk of transmission to mosquitoes and so to other people. However it confers no direct benefit on the individual who takes the drug. Indeed it poses a net risk, since it has side-effects, including the potential for a severe haemolytic reaction (breakdown of red blood cells) in a certain class of individuals (those with genetic G6PD deficiency).  Nevertheless, primaquine is taken as a single dose by millions of people annually.

Cyproterone acetate (CPA) is a testosterone-blocking drug that has been used to ‘chemically castrate’ certain sexual offenders, including paedophiles. It can’t redirect misplaced sexual desires. But it can attenuate them, thereby reducing recidivism. Again, though, it can have serious side effects for the user, including liver damage and possibly depressive mood changes. Still, more than twenty countries allow the use of CPA in sex-offenders, and several US states have authorised the use of a related agent (MPA).

Primaquine and CPA might appear to have little in common. But ethically, there are some interesting parallels. Continue reading

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