The researchers demonstrated in an animal model that the delivery system for the gene, a novel gutted adenoviral vector called HC-Adv, is completely invisible to the immune system. Vectors previously used to deliver genes carried minute amounts of viral proteins that were detected by the immune system, triggering an immune response that rendered the therapeutic gene inactive after a period of weeks.

According to the researchers, this delivery system is safer and more effective than what is currently available, and should therefore advance clinical gene therapy trials for people suffering from central nervous system disorders such as Parkinson's, Alzheimer's, and Multiple Sclerosis. The research was sponsored in part by The National Institutes of Health.

csmc/

Scientists from the Max Planck Institute for Evolutionary Anthropology in collaboration with their colleagues at the universities in Barcelona and Leipzig have now discovered that one percent of the Neanderthals in Europe had red hair - and it was definitely not dyed. The researchers tracked down the Neanderthals' hair colour by means of genetic analysis: first, they attempted to multiply a piece of the mc1r gene from an extract of Neanderthal DNA. In doing so, they found a variant that has never been observed in modern humans.

Thanks to a series of complex tests, the molecular biologists were able to rule out the chance that the experimental samples containing the variant may have been contaminated with modern human DNA, or were a random result caused by damaged DNA or PCR errors (PCR, or polymerase chain reaction, is a method of multiplying DNA). Functional tests then showed that this variant is much less active than the normal human variant. "Gene variants with similarly reduced activity are also known in modern man - although they are a result of other mutations," says Michael Hofreiter. "In people, they lead to red-coloured hair. We can therefore assume that part of the Neanderthal population may have had red or light coloured hair and possibly even lighter coloured skin," according to the paleoanthropologist.

Whether red hair in Neanderthals was considered particularly erotic or more of a turnoff is, of course, something the scientists cannot say.

mpg.de/