A team of researchers led by Dr Erika Sasaki at the Central Institute for Experimental Animals in Kawasaki, Japan has created monkeys that glow, by inserting a gene from jellyfish into their DNA. The research, published in the journal Nature, showed that the transgene was passed on to offspring, an achievement that has not been shown before in primates and which could help advance research in diseases such as Parkinson's and Huntington's.
The gene codes for green fluorescent protein (GFP), which glows green under ultraviolet light. The researchers inserted this gene into a virus and injected it into 91 marmoset embryos, resulting in the birth of five healthy marmosets. All expressed the GFP gene as shown by their glowing feet. The sperm from one of the male transgenic marmosets has now been used to fertilise normal eggs and two more transgenic offspring were produced.
The research shows that it may be possible to breed colonies of monkeys that carry a specific mutation to cause a disease. 'This is a great advancement, and it will bring more attention to primate models from people that do not normally think about primates', Anthony Chan, of the Yerkes National Primate Research Centre of Emory University in Atlanta, Georgia, told Nature news. In 2001 Dr Chan produced 'ANDi', the world's first transgenic rhesus monkey, with Gerald Schatten from the University of Pittsburgh, Pennsylvania.
However, the technique will not be useful for all diseases. Hideyuki Okano, a co-author from the Keio University School of Medicine told BBC News, 'we can just introduce genes by virus vectors, so the limitation comes from the sizes of the genes that can be carried by the retroviruses'.
Marmosets are useful as animal 'models' of disease as they mature rapidly, reproduce often and are closer to humans than rodents. However, they are more distantly related to humans than macaques so it is unclear how well they will model human disease. Dr Chan told Nature, 'they'll be better than rodents, but will they be good enough?'
The announcement has sparked debate over the potential increase in the number of primates used in medical research. Mark Hill, a cell biologist from the University of New South Wales, Australia told BBC News 'As always in this area of research, there needs to be a close linkage between scientific work, ethical issues and regulatory guidelines'.