'Glowing' Transgenic Monkeys Carrying Green Fluorescent Protein Gene Pave Way For New Disease Models

Five transgenic marmoset offspring are born, (a) Hisui, (b) Wakaba, (c) Banko, (d) Kei (left) and Kou (right). When observed in UV, the skin on the soles of the feet glow green. (Credit: E. Sasaki et al 2009)

A transgenic line of monkeys carrying a gene encoding green fluorescent protein fully integrated into their DNA has been created for the first time. The research, published in the journal Nature, marks the first such feat in non-human primates and paves the way for developing new models of human diseases.

Scientists reported the first transgenic monkeys last year — a model of Huntington’s disease — but in these animals, the gene did not fully integrate into the monkey’s own DNA and was not passed down to their offspring. In this report, Erika Sasaki and colleagues used viral DNA as a delivery vehicle to introduce the gene for GFP into the DNA of the common marmoset Callithrix jacchus. They show that the gene integrated into the monkey’s DNA and was successfully passed down to their offspring, which were healthy and all expressed the new gene.

Transgenic mice have contributed immensely to biomedical research, but for many diseases they are too dissimilar from humans for the results to be meaningful. Non-human primates hold great promise for the study of several human diseases, particularly neurological disorders, for which there are currently no appropriate experimental models. This study marks an important milestone on the road to developing the means to investigate these diseases.

In an accompanying news story, Nature News reporter David Cyranoski explains why other transgenic monkeys have failed to reproduce so far, and describes the 5-year Japanese project to develop alternative animal models of which Sasaki’s research is a part. Also in this issue, an editorial calls for researchers working on transgenic primates to go much further than they have so far in articulating the ethical aspects both of their research and its potential applications. Engagement in public discussion is essential to avoid inappropriate regulation.