In the study, researchers from the Karolinska Institute in Stockholm, Sweden, describe how they developed Zorro-LNA to bind with both strands of a gene's DNA simultaneously, effectively disabling that gene. This development has clinical implications for virtually every human condition caused by or worsened by dominant defective genes. Examples include: Huntington's disease, familial high cholesterol, polycystic kidney disease, some instances of glaucoma and colorectal cancer, and neurofibromatosis, among others.

"Zorro-LNA is a new substance that targets DNA and turns off genes," said co-author Edvard Smith of the Karolinska Institute in Sweden. "It has the potential of becoming a new drug for the treatment of human genetic disease."

The findings described in this article significantly raise the possibility that new therapies could arise where defective DNA is deactivated more completely and more thoroughly than ever before. For instance, Zorro-LNA could be used in combination with "RNA interference" (RNAi). Like Zorro-LNA, RNAi has the ability to deactivate genes, but does so by degrading the gene's RNA. In addition, Zorro-LNA could be used to deactivate certain genes in stem cells, which could eventually lead to the development of new cells, tissues, or organs. The discovery of RNAi was recognized by a Nobel Prize award in 2006 to two American scientists.

"This is a major development in the treatment not only of genetic diseases, but also of acquired diseases when microbes or toxins cause genes to go awry" said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "One might say these researchers have found a gene-hunter's Holy Grail for which scientists have been hunting for many years. Zorro-LNA should give us a new, safe way of blocking the effects of errors in our genetic repertoire."

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The transgenic mice used in the study are homozygous for the gene for beta amyloid protein, making it inevitable that they develop an Alzheimer's like disease as they age. In fact, they lose their memory by nine months of age. These animals, together with regular mice without the beta amyloid genes, were acclimated for one week, with as much food and water as they wished, then divided into four groups. Half the Alzheimer's mice, and half the normal mice received 10 mg/kg Simvastatin for seven days, while half of each group only received saline. Each day the mice had two swimming trials in the water maze, giving them a chance to learn how to reach a platform. Food was always available and safety makes taken during the entire trial.

On the seventh day the animals were tested for spatial memory, in other words low long it took them to find the platform. The Alzheimer's mice that received statin were able to find the platform while none of the transgenic mice receiving only saline were able to do so. Normal mice on statin also showed improvement in the time they usually take to reach the platform compared to normal mice on saline. After the maze test, brain tissue then was studied to determine levels of nNOS.

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