The entire Hawaiian population of the peat moss Sphagnum palustre appears to be a clone that has been in existence for some 50, 000 years researchers have discovered. The study is published in New Phytologist. Among the most long-lived of organisms, every plant of the Hawaiian population appears to have been produced by vegetative rather than sexual propagation and can be traced back to a single parent. Surprisingly, the genetic diversity of the Hawaiian clone is comparable to that detected in populations of S. palustre that do propagate sexually and occur across vaster regions. "The genetic diversity of populations occurring on small remote islands is typically much lower than that detected in populations of the same species found on continents and on larger, less isolated islands, " said Eric Karlin, a professor at Ramapo College in Mahwah, New Jersey, USA.
Oxidative stress is the cause of many serious diseases such as cancer, Alzheimer's, arteriosclerosis and diabetes. It occurs when the body is exposed to excessive amounts of electrically charged, aggressive oxygen compounds. These are normally produced during breathing and other metabolic processes, but also in the case of ongoing stress, exposure to UV light or X-rays. If the oxidative stress is too high, it overwhelms the body's natural defences. The aggressive oxygen compounds destroy genetic material, resulting in what are referred to as harmful 8-oxo-guanine base mutations in the DNA. DNA repair mechanism decoded Together with the University of Oxford, Enni Markkanen, a veterinarian in the working group of Prof. Ulrich HÃ bscher from the Institute of Veterinary Biochemistry and Molecular Biology at the University of Zurich has decoded and characterized the repair mechanism for the mutated DNA bases.
Scientists have uncovered a critical genetic mutation in some patients with myelodysplastic syndromes - a group of blood cancers that can progress to a fatal form of leukemia. The research team at Washington University School of Medicine in St. Louis also found evidence that patients with the mutation are more likely to develop acute leukemia. While this finding needs to be confirmed in additional patients, the study raises the prospect that a genetic test could one day more accurately diagnose the disorder and predict the course of the disease. The research is available online in Nature Genetics. The scientists discovered the mutation in a gene known as U2AF1 when they sequenced the entire genome of a 65-year old man with myelodysplastic syndrome that had progressed to leukemia and compared it with the genome of his tumor cells.
A new study has identified a gene mutation that researchers estimate dates back to 11, 600 B.C., making it the second oldest human disease mutation yet discovered. Researchers with the Ohio State University Comprehensive Cancer Center - Arthur G. James Cancer Hospital and Richard J. Solove Research Institute led the study and estimate that the mutation arose in the Middle East some 13, 600 years ago. Only a mutation seen in cystic fibrosis that arose between 11, 000 and 52, 000 years ago is believed to be older. The investigators described the mutation in people of Arabic, Turkish and Jewish ancestry. It causes a rare, inherited vitamin B12 deficiency called Imerslund-GrÃ sbeck Syndrome (IGS). The researchers say that although the mutation is found in vastly different ethnic populations, it originated in a single, prehistoric individual and was passed down to that individual's descendents.
Clinical gene therapy may be one step closer, thanks to a new twist on an old class of molecules. A group of University of Illinois researchers, led by professors Jianjun Cheng and Fei Wang, have demonstrated that short spiral-shaped proteins can efficiently deliver DNA segments to cells. The team published its work in the journal Angewandte Chemie. "The main idea is these are new materials that could potentially be used for clinical gene therapy, " said Cheng, a professor of materials science and engineering, of chemistry and of bioengineering. Researchers have been exploring two main pathways for gene delivery: modified viruses and nonviral agents such as synthetic polymers or lipids. The challenge has been to address both toxicity and efficiency. Polypeptides, or short protein chains, are attractive materials because they are biocompatible, fine-tunable and small.