Wednesday, August 29, 2007

The Fascinating Interconnections of Biomedical Research

For a number of years now I have been investing a good deal of my intellectual energies into reflecting on the ethical, social and legal challenges of the genetic revolution. This revolution raises important and novel challenges for theories of distributive justice. And if we don't begin taking these challenges seriously now, we risk unfairly distributing the by-products of a revolution that could greatly influence important phenotypes (like health, disease, intelligence, etc.).

One important part of my work has been to make some headway on the issue of what prioritarians ought to say about the duty to directly mitigate genetic disadvantage (through, for example, gene therapy). Recall from earlier posts (here and here), The Priority View maintains "that benefiting people matters more the worse off these people are (Parfit, 2000, p. 101)".

If one moves directly from the prescriptions of the Priority View to real policy- which I think is a mistake, especially in a field as novel (and still speculative) as biomedical technology- one might be inclined to take the view that we should focus most of our energies (and resources) on treating severe, early-onset genetic disorders. For these conditions impose severe restrictions on an individual's expected life-time acquisition of the "natural primary goods".

Those who have been following my blog will know that another project of mine (which really developed as a result of my interests in genetics and justice) is the intersection between theory and practice. So I am keen on integrating normative theory with the real world. And when we reflect on the realities we currently face, in the "here and now", numerous constraints and considerations need to come into play before we can derive sage prescriptions concerning what justice demands in terms of directly mitigating genetic disadvantage.

So take the following prioritarian intuition- the greatest urgency should be placed on mitigating the most severe early-onset disorders. A number of real-world constraints complicate this prescription. For example- how rare these disorders often are, the existence of alternative interventions (which may be more cost-effective), the costs of intervention, the likelihood that intervention will be successful, concerns about informed consent, other forms of disadvantage (socio-economic disadvantage), etc.

Grappling with these kinds of issues has convinced me that prioritarians must be pluralistic prioritarians. In other words, the value of priority must be reasonably balanced against other values (like utility), and thus we should strive to achieve judgements that are informed by a "big picture" perspective of the moral landscape (or what I have called "justice-many-things-considered").

Once one integrates one's normative aspirations with real-world empirical insights, we are more likely to arrive at sage prescriptions that can help us transform the status quo into a more fair and humane arrangement.

One of the challenges for my research has been to examine what the prioritarian ought to say about the priority of different biomedical interventions (e.g. therapies, enhancements, etc.), as well as traditional environmental interventions (e.g. opportunities for education, employment, income, etc.). And what I have come to realise is that these issues are much more complex, and fascinating, than I could have ever imagined. And this makes it much harder to figure out what is the right and wrong course of action! (hence the reason why it is important for us to think long and hard about these issues before jumping to hasty conclusions!)

Working in this area has taught me many interesting things. One important thing I have learned is that we must appreciate the diverse and fascinating interconnections of biomedical research. And an article in the latest issue of Nature Genetics brought this point home to me again tonight. The piece is entitled "Cancer drugs to treat birth defects" and it shows how the effort to treat prevalent diseases like cancer can actually aid the development of therapies for serious pediatric syndromes. Here are the some of the details from this fascinating "News and Views" piece:

Cancer drugs to treat birth defects
Andrew O M Wilkie

Identical mutations of the same genes can lead either to congenital malformations or to cancer, depending on their cellular and temporal context. The demonstration of activated RAS-ERK signaling in a mouse model of Apert syndrome suggests that drugs designed to inhibit this pathway in cancer may also delay the progression of several serious pediatric syndromes.

And a brief sample:

Until a few years ago, the title above might have seemed to belong only in the headlines of the tabloid press. However, as the genes mutated in birth defects and cancer have been identified, and the details of how these mutations disturb the regulation of biochemical pathways have been explained, a remarkable convergence in their underlying cellular mechanisms has been uncovered. This is well illustrated in a study by Vivek Shukla, Xavier Coumoul and colleagues1 on page 1145 of this issue. In a mouse model of Apert syndrome in which affected pups normally die within a few weeks with craniofacial malformations, injection of the pregnant mother with a specific signaling inhibitor enables the mutant offspring to survive and even reproduce. Thus, the huge investments into the design of new anticancer drugs might have collateral benefits in the treatment of rare congenital malformations.

....In conclusion, the work of Shukla et al.1 is likely to stimulate considerable further interest in the use of new drug treatments to reduce the complications associated with several pediatric syndromes. Obvious barriers to the successful implementation of such treatments include the prenatal onset of many of the more severe features of these syndromes, the difficulty of identifying them prenatally (especially as they often result from new mutations) and, as illustrated by the present work, the likely need for long-term treatment. But without the cancer connection, even the possibility of therapy for these rare birth defects would be beyond reach owing to the high costs of drug development, safety monitoring and efficacy testing.