It's the last Friday of the month, so as promised, it's time for another post on some interesting scientific studies.
Last month I posted about a vaccine that immunizes and protects mice from the Zika virus. Finally in the print version of Science, the same research group has published on the efficacy of three different versions of their vaccine in rhesus monkeys. The importance of these results cannot be overstated, given that rhesus monkeys are primates. This provides further evidence that humans can be vaccinated against Zika (Phase I clinical trials of a human vaccine are already underway). The vaccination program will also be supplemented by an influx of over one billion dollars that was part of Congress' stopgap budget that was passed this week to fund the government through December 9th. Huech.
Several genome sequencing studies were published this month that shed light on biodiversity on Earth, as well as further our understanding of human migration tens of thousands of years ago. The first is a comprehensive analysis of the mitochondrial DNA sequences of more than 4,500 mammalian and amphibian species from around the world. This analysis provides evidence that biodiversity is greatest in tropical regions (surprise, surprise) and associated with areas that have smaller human footprints (surprise, surprise). I'll note that this is a preliminary, genetic analysis on biodiversity and there is no direct evidence presented here that humans are the cause of the decreased biodiversity discussed in this study. But it's not a stretch of the imagination to think that we are the cause of global decreases in biodiversity. This study is merely the first stop on the road to validating this relationship using genetic approaches.
*Note: in case you haven't heard of the term Anthropocene, that's the epoch we live in now. It means human activity has measurably and directly impacted Earth's geology and global ecosystems.
The second paper details a study that sequenced the genomes of over 80 Aboriginal Australians and closely-related Papuans. It provides strong evidence that when humans first migrated out of Africa there was only one 'Out of Africa' event that gave rise to modern-day humans. This doesn't mean earlier humans didn't venture from Africa before this, but it does imply that all of us living today are descendants from this single 'event' of migration. I think that's amazing and further exemplifies how our genomes are living history books.
A very exciting finding published in Nature concerns the development of the drug aducanumab, a potential therapy for patients with Alzheimer's Disease (AD). Many AD patients suffer from neurodegeneration associated with plaque build-ups in the brain which are caused by a misfolded protein called amyloid-Beta. Aducanumab is currently in clinical trials and the reported findings in this present study indicate successful treatment of these plaques in AD patients using this drug. This could be a major breakthrough in a devastating disease. I'm looking forward to seeing the rest of the clinical trial results and whether this drug gets fast-tracked for approval by the FDA.
The last study I'll talk about today is probably my favorite, if only because it focuses on the tardigrade. The tardigrade is a microscopic water animal that is one of the most resilient animals ever discovered. These things live everywhere, can endure the harshest of environments (even surviving in space), can go decades without food or water, and are all-around bad-asses. Sequencing of the tardigrade genome last year found that almost one-sixth of its entire genetic repertoire was acquired from other species through a process called horizontal gene transfer. Genes from bacteria, fungi, plants, and Archaea were identified in the tardigrade genome. This month, researchers from Japan published findings on a protein identified in the tardigrade genome that protects DNA from damage and may help the tardigrade survive in extreme environments. The protein, called Dsup, was introduced into human cells and protected those cells from X-ray-induced DNA damage. The most exciting part, however, is that the discovery of this protein could be important for finding new methods to prevent DNA damage in humans, such as protecting our skin from sun UV damage and preventing melanoma. Perhaps expressing this gene in our bodies could be useful to promote longer lifespan, since we accumulate DNA damage as we age. Who knows! The biomedical applications could be endless.
Well there you have it, some science for your Friday afternoon.
