Stem Cells Engineered

http://www.ibtimes.co.uk/stem-cells-engineered-using-genome-editing-technology-1482233

This article, by Jayalakshmi K., discusses expanding genome technologies for engineering stem cells. Scientists are hoping for treatments for diseases and to be applied in new/improved medications. Certain methods, such as CRISPR and TALEN can modify DNA by adding, taking away, substituting, or shortening DNA’s gene sequences. However, there is now a new technique (named iPCS) developed at John Hopkins that causes adult cells to preform similar to embryonic stem cells. This allows the adult cells to evolve into certain needed cells. To perform this new technique, the genome editing process uses DNA and RNA bound together by an enzyme to allow scientists to know where to modify.

This article relates to what we have been learning in class about genetic modification and the process taken to insert the desired genes and change DNA sequences. Though the process used in this case is different from the techniques we have studied, scientists edit the DNA sequence to produce the organism with the wanted additional traits in both. We have also studied stem cells; mostly found in the embryo, the cells are able to develop into other cells (Campbell, Neil A., Brad Williamson, and Robin J. Heyden. Biology: Exploring Life). Adults have few stem cells that can make limited new materials (such as tissues), so the development of iPCS will further expand and improve health.

K., Jayalakshmi. "Stem Cells Engineered Using Genome Editing Technology."                       International Business Times RSS. N.p., 7 Jan. 2015. Web. 08 Jan. 2015.

Most Cancers Due to Bad Luck, Not Heredity or Lifestyle

Title: Most Cancers Due to Bad Luck, Not Heredity or Lifestyle
Author: Kevin Mayor
Published: 2 January 2015
Source: http://www.genengnews.com/gen-news-highlights/most-cancers-due-to-bad-luck-not-heredity-or-lifestyle/81250759/

Cancers are all caused by environment, heredity, and bad luck. However, most people with cancer are just unlucky. Cancer is caused by a mutation in DNA. The lifestyle and heredity of a person only influence the probability of the mutation and not the disease itself. Using tobacco and exposure to radiation only add the "bad luck" factor. DNA mutations are completely random. As a result, more resources should be focused on detecting cancer at an early stage. This is the most effective way to eradicate cancer.

This article relates to "Inherited" Cancer. The article says that cancer most likely won't be inherited from a parent. This is because the mutations passed onto children will only increase the risk of cancer. If a child receives a mutation, they will not necessarily develop cancer. Cancer is caused by mutations in DNA and influenced by genes and other mutagens. 

Why are Most of us right handed?

Link:  http://www.bbc.com/future/story/20141215-why-are-most-of-us-right-handed
 by Jason G. Goldman BBC
Published: December 16, 2014

Summary:
Around 85% of humans have a right hand dominance over left handedness, in no instances is left-handedness more prevalent than right handedness. A bias of one side chosen over the other in the use of our limbs begins in the brain, with the left hemisphere controlling the right side of the body, where most large tasks are controlled. The division of neurological labor over hemispheres of the brain is a feature that evolved in most animals over time as a way to carry out multiple tasks at the same time. For instance, it is possible that the left hemisphere became responsible through evolution to carry out routine tasks, such as foraging for food and react to changes in the environment. It has been suggested that when homo sapiens evolved to stand on two legs, their hands became free to develop different sets of skills, resulting in a "strengthening asymmetry" for using tools and performing tasks. This is supported by the fact that when chimps stand on all fours, they show no hand preference. Also, stone tools made 1.5 million years ago, show species wide right-handedness.

This article connects directly to the study of evolution and certain traits evolving to become dominant over others as species adapt to their environment. As human evolution progressed, we began to stand on two legs, which freed up our hands for specified tasks. Through this evolutionary trait, the dominance of one hand over the other evolved in a clear pattern of right-handedness over left-handedness. This particular trait is very interesting because the evolution of the trait is mostly unknown because left-handedness has been shown to not be a drawback in an individuals ability to function. This brings up the question of why right hand dominance has emerged to be much more prevalent than left hand dominance.

Scientists Discover New Mechanism of Protein Synthesis

Scientists Discover New Mechanism of Protein Synthesis
by Sci-News.com

Published: Jan 4, 2015

http://www.sci-news.com/biology/science-new-mechanism-protein-synthesis-02381.html

Summary by Alice Zorn

A group of researchers from Stanford University and University of California discovered that amino acids can be assembled without "blueprints" (DNA and mRNA). The scientists said that the "ribosomes are machines on a protein assembly line, linking together amino acids in an order specified by the genetic code. When something goes wrong the ribosome can stall, and a quality control crew is summoned to the site," the ribosome is then disassembled in order to "clean up the mess" and the blueprint is discarded. The partially-made protein, however, is recycled, and this new study discovered that just before the protein is recycled, Rqc2 (a protein conserved from yeast to man) makes the ribosome add alanine and threonine (two amino acids) repeatedly, and randomly. This new protein might not be what it was intended to be, but it may have a code that signals that it must be destroyed.



This new discovery relates directly to our studies of molecular genetics. During that unit we learned how protein synthesizes with the help of mRNA and the genetic code, and this new information will further our understanding of the importance of ribosomes in the process, and the difference between successful synthesis and unsuccessful synthesis. This study also shows how much biologists still have to learn about biology, and how science is always changing.

New Perspective on Snake Evolution

http://phys.org/news/2015-01-perspective-snake-evolution.html
Nature Journal
January 5, 2015

Jason Head's and P. David Polly's recent study of the snake skeleton has revealed new information on how they may have evolved. We previously believed that snakes evolved from their lizard ancestors to a more simplified form. Now, it is becoming considered that other animals and lizards gained a more complex skeleton instead. This is due to the finding of distinctions among vertebral bones in the snake's skeleton identical to those of four-legged lizards. This ties to the function of Hox genes in the snakes. Hox genes regulate growth of the neck, trunk, lumbar, sacral and tail regions of limbed animals. Before, it was thought that the function of these genes was disrupted in snakes, resulting in no limbs and a simplified skeleton. It was then thought that the absence of limbs resulted in the loss of the distinction between the shape of the vertebrae in their backbones and neck, trunk, and lumbar regions. However, Head's and Polly's study revealed distinctions in the snake skeleton's vertebrae  similar to the ones in lizards and mice. If the Hox genes were really disrupted in snakes, then their vertebrae would all be similar shapes and sizes, but they were not. Further investigation showed that the regions with Hox genes in snakes matched those in lizards, revealing that these genes in snakes simply control more simple and gradient changes in shape instead of the complex patterned ones in mice and lizard skeletons. It isn't that snakes simplified, it's that mammals and birds have gained more complex skeletal and Hox regions. This completely contrasts what was originally believed about snake evolution.

This new discovery is very important to science and directly relates to what we have been learning in the evolution unit. Scientists now have a better understanding of how reptiles may have evolved, which could lead to further investigation and discovery of the evolution of different animals and/or species. Although their evolution isn't what we had expected and originally predicted, snakes did change over the course of a long time from their lizard ancestors. This evolution was likely due to the need to survive in a different environment from the one lizards lived in. This new body shape for the snakes could help them catch food, escape predators, and blend in to different surroundings, and has evidently been working for them, as they have thrived in many areas. This also relates to how the study of bones and fossils can lead to great evolutionary discoveries, as we have learned in class. Overall, it is a great new point of view that helps us as students as well as other scientists learn more about evolution.

Cancer-Preventing GM Potato Approved

Genetically Modified Potato Approved                                                                                                              Anna Rychlik P6

Link: http://www.nytimes.com/2014/11/08/business/genetically-modified-potato-from-simplot-approved-by-usda.html?_r=0

Date: November 7, 2014

Author: Andrew Pollack


         This article is explaining that a new variety of genetically modified potato has been approved by the U.S.D.A. This potato has been altered so that when it is fried, poteientally dangerous amounts of a (cancer causing) chemical called acrylamide, are not created by the potato. In addition, this new type of potato can also resist bruising. Later in the article, it is questioned wether or not these new potatoes will actually sell. It is argued that in the past, GM potatoes have caused great contraversy with consumers in the US, but these GM potatoes could potentially flourish because of the fact that they are genetically modified to not only help the growers, but the people eating them.
          This relates to what we have been learning in class in the GMO lab we did and the report we wrote up after. This also relates directly to the video we watched about how GM potatoes were not recived well by the general public.

A Second Miller-Urry Experiment

Article: The Origins of Life, by Helen Fields. Published by Smithsonian Magazine
http://www.smithsonianmag.com/science-nature/the-origins-of-life-60437133/?all

The Miller-Urry experiment was widely hailed as a milestone in origin of life research, for it showed a verifiable way for the generation of amino acids and other required biological building blocks to be generated by natural phenomena. However, the two assumed energy sources, ultraviolet light and lightning, only act on the surface of the planet, which, at the time life evolved, was most likely not a hospitable place. Due to the lack of free oxygen, there was no ozone layer to prevent the damaging ultraviolet rays from making it to the surface and smashing up the slowly accumulating (or so is hypothesized) fragile complex organic molecules. However, this article presents an alternative way: the building blocks of life could have been formed at the high heats and pressures around geothermal vents, deep under the ocean, protected from ultraviolet radiation (and the asteroids of the LHB) by kilometers of water. With a much less volatile environment, the complex molecules would have had a chance to form protected.
The article also gives insights into how those basic molecules could have bumped into each other enough to form the polymers of life. The prebiotic soup that was the starting point of life could not have been very concentrated, so much so that randomly floating monomers forming polymers has been described as "infinitesimally small." However, if the molecules were sliding along a surface, all of a sudden this becomes a two-dimensional instead of three-dimensional problem, making an interaction much more likely. It would also reduce the amount of space the molecules had to work in from the whole ocean to just the surface itself, reducing the search space. These researchers are investigating to see if certain rocks might have been able to do that with amino acids or other monomers. If so, that's another lot of improbability in the origin of life accounted for.
Yet, like all articles on the origin of life I have seen, it does not address the real issue with the RNA world hypothesis, the one currently accepted by most researchers. Despite there being plausible hypothesis for the generation of basic biological monomers, there remains the problem: How do we get this first replicating molecule? According to this article: http://www.nature.com/nature/journal/v515/n7527/pdf/nature13900.pdf, the best that has been done that had a limited capacity to self-replicate when given the proper starting components (those components is another moderately improbable "if"), is 83 bases in length. It requires 1 ribozyme (enzyme made of RNA) and 1 template strand, which is the same thing as the enzyme. Probability-wise, if there are 8 possible bases (U, A, G, C in both left-handed and right-handed forms http://en.wikipedia.org/wiki/Chirality), and a specific sequence of 83 bases to follow, the number of possible sequences is 8^83, which is approximately 10^75. Taking in mind that we need 2 of these, one as ribozyme and one as template, we need to multiply again for the two sequences: 10^75*10^75=10^150. This is the same as the number of actions the universe could have taken in its entire lifetime, (http://en.wikipedia.org/wiki/Universal_probability_bound) of 10^150 possible actions. In other words, if the whole universe attempted to find, by random processes, two specific sequences of 83 bases each, it could, if if every possible action it took searched one possible combination. Note that this is, of course, a wild overestimation on the probabilistic resources that could be brought to bear on the problem of the origin of life, and the estimate of 10^150 possible actions assumes a search time of about 1 billion times longer that the age of the universe. That, it seems to me, is the real problem with our current understanding of the origin of life.