The real value of embryonic stem cells?

As with many important scientific discoveries, embryonic stem (ES) cells came onto the scene long before the media and most of the rest of us became intensely interested in the subject. The first articles on the isolation of mouse ES cells were published in 1981¹ immediately heralding the possibility of isolating ES cells from other mammals. During the mid- to late-nineties, this possibility was realised, with the isolation of ES cells from various species including rabbit, pig, cow, and primates (monkey and marmoset), culminating with the publication in 1998 of two articles on the isolation of human ES cells².

<>The value of ES cells can be understood quite well by delving back to their origins in the early eighties. Since that time, these cells have given us a wealth of information of how mammalian embryos, including human babies, develop in the womb and how development continues following birth. Just as importantly, research on these cells has been providing us with what happens when foetal development goes wrong, either because of a genetic defect or one that is imposed, for example, by a chemical or drug. The real value of over two decades of ES-cell research currently lies with these advances but there has been relatively little ‘external’ acclaim or general interest. This is a pity, since this basic scientific endeavour has played positively into a wide range of fields of interest to all of us, including human and animal toxicology, assisted human reproduction, livestock breeding, and the molecular basis of disease.

<> Instead, as we know, interest and debate has centred largely on the ethics and morals of using human ES cells to treat, potentially, a range of human diseases, many of which are virtually intractable with respect to a cure. While some extol the virtues of pursuing the science, others want a line to be drawn in the sand. Debate has frequently become obscured when, for example, a scientist with little training in ethics ventures into the morals of the issue, and equally, when ethicists begin to pick apart the quality of the science. These debates will, and must, rage on but it interesting that two things in particular seem to be lost to most debates on the issue: (i) the value of research to this point in time, and (ii) the likelihood that the use of stem cells of any type to treat most if not all these diseases remains, for a variety of reasons, a distant possibility. <>

<> No doubt, your own views will come thick and fast. In future articles, I will briefly explore some of these issues further.

² JA Thomson et al. (1998) Science 282, 1145; Shamblott et al. (1998) Proceedings of the National Academy of Sciences USA 95, 13726.