Transgenic primate poised to be new lab rat

Nature 27 May, has papers and editorial on the first transgenic primate that has passed on its transgene to the next generation (a transgene is the new or foreign gene inserted into the genome).  (See abstract of Nature News article at GNTIS ) 

Achieving this opens the door to a better human disease model – better than the existing mouse anyway.

The primate in question is a marmoset, one that is genetically a long way from humans compared to macaques, the primate of choice at the moment for understanding human disease.  The problem is that nobody has managed to get a transgenic macaque to pass on its genes, which is the important thing if you are trying to understand human disease, the genes involved and how they influence the disease and its progression through the generations, and to test drugs and other treatments on. 

So the success with the marmoset has got a few people excited. There is concern that the marmoset’s brain is too primitive in primate terms to be much better than a mouse when investigating neuronal diseases or diseases such as Parkinson’s or Alzheimer’s, but this has yet to be determined.

What I think may be the biggest hurdle is the ethical issue of genetically modifying a primate to have a human disease and purposely breeding these for research.

I am sure there will be a few people, and especially animal rights groups, seething once they digest the story.  But we have managed to create transgenic human-disease models in mice.  We have seemingly accepted this, however, if my very anecdotal evidence gathered from a few years of public engagement activities is anything to go by then we will be less inclined to accept such genetic tinkering with primates, even one such as the marmoset – which are small, cute and lacking many of the anthropomorphic characteristics of the higher primates. 

And should the marmoset not prove particularly useful as a human disease model, we are already trying to repeat the outcome with macaques, so transgenic primates that are genetically closer to us won’t be too far away.

Why do we (if indeed we do) have an aversion to doing this sort of thing with higher primates – or any primate?  And I am chasing something deeper than, “because they are like humans”.

Genetically, we are 80% the same as a mouse, or 66% the same as a fruit fly.  Why don’t we get as upset when we create transgenic disease models from these species, generally speaking that is, as there are some people that are against this?

If there is a huge backlash against this, will that backlash remain, if the creation of such a transgenic primate can suddenly give us new insight into the understanding and treatment of human disease?

Me and my family are healthy, so I can easily sit back and say it is wrong simply based on what the bioethicist, Leon Kass coined, ‘the wisdom of repugnance’. Or as I prefer, the ‘Yuk factor’.  This is where I feel something is wrong, but don’t know why.  I know where he is coming from, but I don’t agree it is always a good ethical guide.

But I honestly can’t say, if my opinion would change should I or a family member was suddenly diagnosed with something, in which research using transgenic primates might reveal a successful treatment – even cure?

If we accept the marmoset in the same way we accept the mouse, will be accept the macaque?  If we accept the macaque, would we accept the chimpanzee, our closet primate relative?  How much and what are we prepared to sacrifice in our attempts to treat serious human disease?  Just my rambling thoughts really on this, but it is a conversation that crops up on a regular basis to which I find myself struggling to establish a personal position on.

Jason Major

Manager, GNTIS

Reference:

Leon Kass: The New Republic, Vol 216, p.17