Category Archives: Genetic Engineering

A new gene-editing technique could lead to more useful animal models of disease, and perhaps one day more effective gene therapy for humans

Genetically modified long-tailed macaques. Credit: Cell, Niu et al.

Like many babies, the wide-eyed twins are cute. The fact that they are macaque monkeys is almost beside the point. What is not beside the point, however, is their genetic heritage. These baby macaques are, as reported inCell, the first primates to have been genetically modified using an extremely precise gene-editing tool based on the so-called CRISPR/Cas system.

Conducted by researchers in China, the new study is significant because it paves the way for the custom development of laboratory monkeys with genetic profiles that are similar to those found in humans with certain medical disorders. Although mice and rats have long been the animals of choice when creating living models of human disease, they have not been very helpful for studying neurological conditions such as autism and Alzheimers disease; the differences between rodent and human brains are just too great.

To be sure, a few other genetically modified monkeys have been born over the past decade and a half, but the methods used to alter their DNA were not as efficient or as easy to use as the CRISPR/Cas technology. The amount of genome engineering in monkeys is pretty small, says George Church, a professor of genetics at Harvard Medical School.So yes, this [paper] is a pretty big deal.

CRISPR stands for clustered regularly interspaced short palindromic repeats and refers to what at first glance appear to be meaningless variations and repeats in the sequence of molecular letters (A, T, C and G) that make up DNA. These CRISPR patterns are found in many bacteria and most archaea (an ancient group of bacteria that is now considered to be different enough from other one-celled organisms to merit is own taxonomic kingdom, along with bacteria, protists, fungi, plants and animals).

First identified in bacteria in 1987, CRISPR elements started being widely used to create genetic engineering tools only in 2013. It took that long to figure out that the patterns actually served a purpose, determine out what that purpose washelping archaea and bacteria to recognize and defend themselves against virusesand then adapt that original function to a new goal.

Basically, biologists learned that certain proteins associated with the CRISPR system (dubbed, straightforwardly enough, CRISPR-associated, or Cas, proteins) act like scissors that cut any strands of DNA they come across. These cutting proteins, in turn, are guided to specific strands of DNA by complementary pieces of RNA (a sister molecule to DNA). The bacteria generate specific guide strands of RNA whenever they encounter a virus that is starting to hijack their cellular machinery. The guide-RNA complements the viral DNA, which is how the Cas proteins know where to cut. The bacteria then keep a copy of the viral DNA in their own genetic sequence between two CRISPR elements for future reference in case a similar virus tries to cause trouble later on.

In the past couple of years researchers have learned how to trick the Cas proteins into targeting and slicing through a sequence of DNA of their own choosing. By developing strands of RNA that precisely complement the part of the DNA molecule that they want to change, investigators can steer the Cas proteins to a predesignated spot and cut out enough genetic material to permanently disrupt the usual expression of the DNA molecule at that location.

In essence, scientists have turned a bacterial self-defense mechanism into an incredibly precise gene-editing tool. By some accounts CRISPR technology has been successfully tried out on 20 different kinds of higher organisms (meaning higher than bacteria) in just the past year or so.

Link:
New Biotech Makes It Much Easier to Genetically Modify Monkeys

A central question has been answered regarding a protein that plays an essential role in the bacterial immune system and is fast becoming a valuable tool for genetic engineering. A team of researchers with the Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have determined how the bacterial enzyme known as Cas9, guided by RNA, is able to identify and degrade foreign DNA during viral infections, as well as induce site-specific genetic changes in animal and plant cells. Through a combination of single-molecule imaging and bulk biochemical experiments, the research team has shown that the genome-editing ability of Cas9 is made possible by the presence of short DNA sequences known as "PAM," for protospacer adjacent motif.

"Our results reveal two major functions of the PAM that explain why it is so critical to the ability of Cas9 to target and cleave DNA sequences matching the guide RNA," says Jennifer Doudna, the biochemist who led this study. "The presence of the PAM adjacent to target sites in foreign DNA and its absence from those targets in the host genome enables Cas9 to precisely discriminate between non-self DNA that must be degraded and self DNA that may be almost identical. The presence of the PAM is also required to activate the Cas9 enzyme."

With genetically engineered microorganisms, such as bacteria and fungi, playing an increasing role in the green chemistry production of valuable chemical products including therapeutic drugs, advanced biofuels and biodegradable plastics from renewables, Cas9 is emerging as an important genome-editing tool for practitioners of synthetic biology.

"Understanding how Cas9 is able to locate specific 20-base-pair target sequences within genomes that are millions to billions of base pairs long may enable improvements to gene targeting and genome editing efforts in bacteria and other types of cells," says Doudna who holds joint appointments with Berkeley Lab's Physical Biosciences Division and UC Berkeley's Department of Molecular and Cell Biology and Department of Chemistry, and is also an investigator with the Howard Hughes Medical Institute (HHMI).

Doudna is one of two corresponding authors of a paper describing this research in the journal Nature. The paper is titled "DNA interrogation by the CRISPR RNA-guided endonuclease Cas9." The other corresponding author is Eric Greene of Columbia University. Co-authoring this paper were Samuel Sternberg, Sy Redding and Martin Jinek.

Bacterial microbes face a never-ending onslaught from viruses and invasive snippets of nucleic acid known as plasmids. To survive, the microbes deploy an adaptive nucleic acid-based immune system that revolves around a genetic element known as CRISPR, which stands for Clustered Regularly Interspaced Short Palindromic Repeats. Through the combination of CRISPRs and RNA-guided endonucleases, such as Cas9, ("Cas" stands for CRISPR-associated), bacteria are able to utilize small customized crRNA molecules (for CRISPR RNA) to guide the targeting and degradation of matching DNA sequences in invading viruses and plasmids to prevent them from replicating. There are three distinct types of CRISPR-Cas immunity systems. Doudna and her research group have focused on the Type II system which relies exclusively upon RNA-programmed Cas9 to cleave double-stranded DNA at target sites.

"What has been a major puzzle in the CRISPR-Cas field is how Cas9 and similar RNA-guided complexes locate and recognize matching DNA targets in the context of an entire genome, the classic needle in a haystack problem," says Samuel Sternberg, lead author of the Nature paper and a member of Doudna's research group. "All of the scientists who are developing RNA-programmable Cas9 for genome engineering are relying on its ability to target unique 20-base-pair long sequences inside the cell. However, if Cas9 were to just blindly bind DNA at random sites across a genome until colliding with its target, the process would be incredibly time-consuming and probably too inefficient to be effective for bacterial immunity, or as a tool for genome engineers. Our study shows that Cas9 confines its search by first looking for PAM sequences. This accelerates the rate at which the target can be located, and minimizes the time spent interrogating non-target DNA sites."

Doudna, Sternberg and their colleagues used a unique DNA curtains assay and total internal reflection fluorescence microscopy (TIRFM) to image single molecules of Cas9 in real time as they bound to and interrogated DNA. The DNA curtains technology provided unprecedented insights into the mechanism of the Cas9 target search process. Imaging results were verified using traditional bulk biochemical assays.

"We found that Cas9 interrogates DNA for a matching sequence using RNA-DNA base-pairing only after recognition of the PAM, which avoids accidentally targeting matching sites within the bacterium's own genome," Sternberg says. "However, even if Cas9 somehow mistakenly binds to a matching sequence on its own genome, the catalytic nuclease activity is not triggered without a PAM being present. With this mechanism of DNA interrogation, the PAM provides two redundant checkpoints that ensure that Cas9 can't mistakenly destroy its own genomic DNA."

Story Source:

Read this article:
Puzzling question in bacterial immune system answered

Can Animals Do Human Things Better Than Humans?
See more at / Subscribe for more every day Profound Photo Experiment: X Animals Doing Human Things Better Than Humans Check out Fail Compilations: Original ...

By: SuperFunnyshop

Read this article:
Can Animals Do Human Things Better Than Humans? - Video

November 2013 Breaking News Hybrid human animal Genetic Hybrid Engineering 4 of 5 Last Day
Here the latest videos, follow us . Please, Subscribe November 2013 Breaking News Labs Mixing Human DNA with Animal DNA 4 of 5 Last days final hour news prop...

By: Posledniye Novosti

Originally posted here:
November 2013 Breaking News Hybrid human animal Genetic Hybrid Engineering 4 of 5 Last Day - Video

PUBLIC RELEASE DATE:

28-Jan-2014

Contact: Vicki Cohn vcohn@liebertpub.com 914-740-2100 Mary Ann Liebert, Inc./Genetic Engineering News

New Rochelle, NY, January 28, 2014Modern combat and the global war on terror, with increased use of improvised explosive devices, have led to a nearly 350% increased rate of genitourinary injuries. The often debilitating long-term sexual, psychological, fertility, and hormonal effects of these traumatic wounds and the need for new coordinated approaches to care are the focus of a Review article and Guest Editorial in Journal of Men's Health, a peer-reviewed publication from Mary Ann Liebert, Inc., publishers. The articles are available free on the Journal of Men's Health website at http://www.liebertpub.com/jmh.

The Review "Genitourinary Trauma in the Modern Era of Warfare" discusses why battlefield genitourinary injuries have increased so dramatically in recent years and how they have changed. The article is coauthored by Justin Han, MD and Chris Gonzalez, MD, MBA, Northwestern University Feinberg School of Medicine and Jesse Brown Veterans Affairs Medical Center (Chicago, IL), and Mark Edney, MD, Peninsula Urology Associates (Salisbury, MD) and Lieutenant Colonel, U.S. Army Reserve, 48th Combat Support Hospital (Ft. Meade, MD).

Janice Bray, MD, MBA, Chief, Central Texas Veterans Health Care System (Temple, TX), describes the potentially devastating physical, psychological, and social impact of these combat woundsand in particular their effects on future relationships, intimacy, parenting, self-worth, and suicide riskin the guest editorial "Genitourinary Trauma: A Battle Cry for Integrated Collaborative Veteran-Centric Care."

###

About the Journal

Journal of Men's Health is the premier peer-reviewed journal published quarterly in print and online that covers all aspects of men's health across the lifespan. The Journal publishes cutting-edge advances in a wide range of diseases and conditions, including diagnostic procedures, therapeutic management strategies, and innovative clinical research in gender-based biology to ensure optimal patient care. The Journal addresses disparities in health and life expectancy between men and women; increased risk factors such as smoking, alcohol abuse, and obesity; higher prevalence of diseases such as heart disease and cancer; and health care in underserved and minority populations. Journal of Men's Health meets the critical imperative for improving the health of men around the globe and ensuring better patient outcomes. Tables of content and a sample issue can be viewed on the Journal of Men's Health website at http://www.liebertpub.com/jmh.

About the Societies

See the original post here:
Impact of battlefield-related genitourinary injuries described in Journal of Men's Health

Ban Genetic Engineering For Unborns
Re-Upload.

By: Akira Talk Show

Originally posted here:
Ban Genetic Engineering For Unborns - Video

Continue reading page |1|2 |3

(Image: Kotryna Zukauskaite)

A simple, very powerful method is making genome editing much easier and faster prepare for a revolution in biology and medicine

SEQUENCING genomes has become easy. Understanding them remains incredibly hard. While the trickle of sequence information has turned into a raging torrent, our knowledge isn't keeping up. We still have very little understanding of what, if anything, all our DNA does.

This is not a problem that can be solved by computers. Ultimately, there is only one way to be sure what a particular bit of DNA does you have to alter it in real, living cells to see what happens. But genetic engineering is very difficult and expensive.

At least, it used to be. Last month, two groups announced that they had performed a mind-boggling feat. They targeted and disabled nearly every one of our genes in cells growing in a dish. They didn't knock out all the genes in each cell at once, of course, but one gene at a time. That is, they individually modified a staggering 20,000 genes. "It's truly remarkable," says Eric Lander, director of the Broad Institute of MIT and Harvard, who led one of the studies. "This is transformative."

To put it into perspective, in 2007 an international project was launched to target and "knock out" each of the 20,000 genes a mouse possesses. It took the collective effort of numerous labs around the world more than five years to complete, and it cost $100 million. Now two small teams have each done something similar in a fraction of the time and cost. The secret: a simple and powerful new way of editing genomes. The term breakthrough is overused, but this undoubtedly is one. "It's a game-changer," says Feng Zhang, also at the Broad Institute, who led the other study.

The technique, unveiled just a year ago, is generating tremendous excitement as its potential becomes clear. It is already starting to accelerate the pace of research Lander and Zhang used it to find out which genes help cancer cells resist a drug, for instance. In years to come, it is likely to be used in gene therapy, and to create a new generation of genetically engineered organisms with extensive but precise changes to their genomes. And if we ever do decide to genetically modify people, this is the tool to do it with.

While genetic engineers have done some amazing things, their first tools were very crude. They bombarded cells with extra DNA sometimes literally in the hope that it might occasionally get added to a cell's genome. But there was no way to control where in the genome it went, and if added DNA ends up in the wrong place it can cause havoc. Also, this approach does not allow for any tinkering with existing genes, which is the key to finding out what they and their variants do.

So in the past couple of decades the focus has switched to genome editing. To visualise how it works, imagine the genome as a collection of cookbooks written on long scrolls of paper and cared for by blind librarians. The librarians try to repair any damage but because they can't read they are easily tricked.

View original post here:
Right on target: New era of fast genetic engineering

AP Bio Genetic Engineering Survey
AP Bio Genetic Engineering Survey.

By: Matthew C

Go here to see the original:
AP Bio Genetic Engineering Survey - Video

Inject a gene from a certain cold-water fish into a strawberry, and the strawberry can withstand colder temperatures. But would you still want to eat it?

Such advances in genetic engineering have implications for helping feed a growing, hungry world but a lot of people aren't too keen on eating those advances just yet.

Others wouldn't hesitate.

The difference reflects the "wild, messy debate" surrounding genetically modified food, with one of the more recent skirmishes centering on whether food labels should contain information about such ingredients, according to Nick George, president of the Midwest Food Processors Association, based in Madison.

Wisconsin's agriculture and food production industries find themselves smack in the middle of the debate.

"This is a big issue," George said. "It's not going away."

Neither, it seems, are genetically engineered crops in the American food chain.

The U.S. Department of Agriculture estimates that 93% of soybean acres and 85% of corn acres in 2013 were planted with genetically modified, herbicide-tolerant crop varieties.

The percentage of insect-resistant corn planted in 2013 stood at 76%, according to the USDA. The insect-resistant corn contains a gene from the soil bacterium Bt Bacillus thuringiensis. The bacteria produce a protein that is toxic to specific insects.

Consider that there are nearly 1.3 million dairy cows in Wisconsin, and some of them are no doubt eating corn with genetically modified ingredients.

See more here:
Debate rages over labeling genetically modified food

PUBLIC RELEASE DATE:

27-Jan-2014

Contact: Vicki Cohn vcohn@liebertpub.com 914-740-2100 Mary Ann Liebert, Inc./Genetic Engineering News

New Rochelle, NY, January 27, 2014Building on previous evidence showing that religious belief involves cognitive activity that can be mapped to specific brain regions, a new study has found that causal, directional connections between these brain networks can be linked to differences in religious thought. The article "Brain Networks Shaping Religious Belief" is published in Brain Connectivity, a bimonthly peer-reviewed journal from Mary Ann Liebert, Inc., publishers, and is available free on the Brain Connectivity website at http://www.liebertpub.com/brain.

Dimitrios Kapogiannis and colleagues from the National Institute on Aging (National Institutes of Health, Baltimore, MD) and Rehabilitation Institute of Chicago, IL, analyzed data collected from functional magnetic resonance imaging (fMRI) studies to evaluate the flow of brain activity when religious and non-religious individuals discussed their religious beliefs. The authors determined causal pathways linking brain networks related to "supernatural agents," fear regulation, imagery, and affect, all of which may be involved in cognitive processing of religious beliefs.

"When the brain contemplates a religious belief," says Dr. Kapogiannis, "it is activating three distinct networks that are trying to answer three distinct questions: 1) is there a supernatural agent involved (such as God) and, if so, what are his or her intentions; 2) is the supernatural agent to be feared; and 3) how does this belief relate to prior life experiences and to doctrines?"

"Are there brain networks uniquely devoted to religious belief? Prior research has indicated the answer is a resolute no," continues study co-author Jordan Grafman, Director, Brain Injury Research and Chief, Cognitive Neuroscience Laboratory, Rehabilitation Institute of Chicago. "But this study demonstrates that important brain networks devoted to various kinds of reasoning about others, emotional processing, knowledge representation, and memory are called into action when thinking about religious beliefs. The use of these basic networks for religious practice indicates how basic networks evolved to mediate much more complex beliefs like those contained in religious practice."

###

About the Journal

Brain Connectivity is the journal of record for researchers and clinicians interested in all aspects of brain connectivity. The Journal is under the leadership of Founding and Co-Editors-in-Chief Christopher Pawela, PhD, Assistant Professor, Medical College of Wisconsin, and Bharat Biswal, PhD, Chair of Biomedical Engineering, New Jersey Institute of Technology. It includes original peer-reviewed papers, review articles, point-counterpoint discussions on controversies in the field, and a product/technology review section. To ensure that scientific findings are rapidly disseminated, articles are published Instant Online within 72 hours of acceptance, with fully typeset, fast-track publication within 4 weeks. Tables of content and a sample issue may be viewed on the Brain Connectivity website at http://www.liebertpub.com/brain.

The rest is here:
Do brain connections help shape religious beliefs?