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.Source: Science Daily Researchers at K.U. Leuven and Harvard University show that stretches of DNA previously believed to be useless 'junk' DNA play a vital role in the evolution of our genome. They found that unstable pieces of junk DNA help tuning gene activity and enable organisms to quickly adapt to changes in their environments. The results will be published in the journal Science.Junk DNA "Most people do not realize that all our genes only comprise about 3% of the total human genome. The rest is basically one large black box," says Kevin Verstrepen, heading the research team. "Why do we have this DNA, what is it doing?"Scientists used to believe that most of the DNA outside of genes, the so-called non-coding DNA, is useless trash that has sneaked into our genome and refuses to leave. One commonly known example of such 'junk DNA' are the so-called tandem repeats, short stretches of DNA that are repeated head-to-tail. "At first sight, it may seem unlikely that this stutter-DNA has any biological function," says Marcelo Vinces, one of the lead authors on the paper. "On the other hand, it seems hard to believe that nature would foster such a wasteful system."Unstable repeats The international team of scientists found that stretches of tandem repeats influence the activity of neighboring genes. The repeats determine how tightly the local DNA