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Category Archives: Transhuman News

How head-on collisions of DNA protein machines stop replication – Phys.Org

Posted: August 15, 2017 at 11:47 am

August 15, 2017 A schematic showing how R-loops, a hybrid of RNA and DNA, can form during DNA transcription when the messenger RNA chain being assembled by the RNA polymerase binds to one of the DNA strands. R-loops effectively block replication. Credit: Merrikh lab/UW Medicine

A new study describes how head-on collisions between protein machines on chromosomes can disrupt DNA replication and boost the rate of gene mutations that help bacteria survive hostile environments, resist antibiotics, and blunt attacks by immune defenses.

The study appears in the journal Cell.

Houra Merrikh, assistant professor of microbiology at the University of Washington School of Medicine in Seattle, led the research group.

She said that the findings suggest these head-on collisions are part of a process by which bacteria control their evolution by accelerating mutations in key genes involved in coping with new conditions.

"These collisions may serve as a mechanism to promote adaptation under conditions that are critical in a bacterium's life, such as adapting to environmental stresses or, in the case of disease-causing bacteria, to conditions within a host cell during infection" Merrikh said.

The study researchers looked at collisions that occur between two types of molecular machines, large protein complexes that crawl along chromosomes as they "read" the genetic instructions coded in the sequence of the chromosomes DNA.

One of these machines, called RNA polymerase, uses the instructions encoded in genes to assemble a chain of RNA, called messenger RNA (referred to as mRNA). The cell will use this chain as a template to synthesize proteins, a process called transcription.

The job of the other machine, called a replisome, is to make a copy of the chromosome during cell division, a process called replication. This gives both of the cell's offspring its own chromosome. During each of these processes the two strands of the double-stranded DNA must be opened so that the DNA sequences containing the genetic code can be read.

Because most genes are oriented for replication, these machines usually travel in the same direction as they work their way along the chromosome. Because the replisomes travel faster, they sometimes overtake the slower RNA polymerase and cause a rear-end collision.

Although these collisions can interfere with replication, the disruption is usually minor. In those cases, cells have mechanisms to rapidly resolve these problems.

However, there are some genes that are coded within the chromosome "backwards." When these genes need to be expressed, the RNA polymerase must travel in the opposite of the usual direction, and a head-on collision between the RNA polymerase and replisome occurs.

These head-on collisions turn out to have a much greater impact on replication and transcription. They also increase the frequency of genetic errors in these "backwards" genes.

Previous research has suggested that two machines come to a halt because they actually come into direct contact, or as they approach each other, the DNA between them twists into tight coils, thereby checking their progress.

While these may be factors, in the new study, UW researchers demonstrate that another mechanism might explain why head-on collisions are so disruptive and how they increase the formation of mutations in some genes.

What the researchers found was that when these collisions occur, the messenger RNA chain being assembled by the RNA polymerase actually binds to one of the DNA strands behind it. That strand had been opened during the transcription process. This binding creates a RNA:DNA hybrid, called an R-loop (for RNA-loop), which effectively blocks replication.

The researchers found the blockade is so effective that, without an enzyme that removes R-loops, the bacteria die.

But why do these backward head-on genes exist if they pose such a threat? It turns out that most of these head-on genes are ones that are turned on when the bacteria are under stress, for example, when they are exposed to a hostile environment.

Merrikh and her colleagues postulate that in these high-stress situations, the head-on collisions increase mutations in these stress response genes. Some of these mutations can increase the chances that bacterium's offspring will survive and thrive under similar conditions in the future.

Kevin Lang, a postdoctoral fellow in the Merrikh lab, and first author on the study, said the mechanism appears to be a trade-off: Bacteria accept that while the head-on collisions disrupt replication and increase harmful mutations, they also promote the potential for beneficial mutations in key genes that will allow them to survive in difficult conditions.

"One of the bacteria we studied, Listeria monocytogenes, can live in the various environments like salty foods in your refrigerator, or, when you get infected, in your cells," he explained "In order to survive in so many niches, you have to be able to evolve and evolve quickly."

Explore further: Head-on collisions between DNA-code reading machineries accelerate gene evolution

More information: Kevin S. Lang et al, Replication-Transcription Conflicts Generate R-Loops that Orchestrate Bacterial Stress Survival and Pathogenesis, Cell (2017). DOI: 10.1016/j.cell.2017.07.044

Journal reference: Cell

Provided by: University of Washington

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Color in the plant kingdom is not merely a joy to the eye. Colored pigments attract pollinating insects, they protect plants against disease, and they confer health benefits and are used in the food and drug industries. A ...

A new study describes how head-on collisions between protein machines on chromosomes can disrupt DNA replication and boost the rate of gene mutations that help bacteria survive hostile environments, resist antibiotics, and ...

There is a rising risk of human and domestic animal exposure to deadly Hendra virus (HeV) carried by fruit bats in Eastern Australia due to human intrusion into their habitats, human proximity to woodlands and vegetation ...

Centuries ago, the ancient networks of the Silk Road facilitated a political and economic openness between the nations of Eurasia. But this network also opened pathways for genetic exchange that shaped one of the world's ...

Chromatin remodelersprotein machines that pack and unpack chromatin, the tightly wound DNA-protein complex in cell nucleiare essential and powerful regulators for critical cellular processes, such as replication, recombination ...

The emergence in recent years of the first mammalian haploid cell lines has raised great expectations in the scientific community. Despite their potential, these cultures present some issues that complicate their use because ...

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How head-on collisions of DNA protein machines stop replication - Phys.Org

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45 bodies recovered from Marawi up for DNA tests: PNP – ABS-CBN News

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MANILA The Philippine National Police crime laboratory on Tuesday reported the retrieval of 45 bodies from Marawi City, which will undergo DNA examinations.

Thirty-five of the bodies were retrieved by the PNP's Scene of Crime Operation (SOCO) teams and 10 by the Armed Forces of the Philippines.

Supt. Ramos Bergonio, PNP Crime Laboratory operations head, said his unit has begun processing the bodies and collecting antemortem data consisting of buccal swabs for DNA examination, as well as gathering personal information from immediate claimants of the bodies.

To date, Bergonio said there was no recorded match on DNA examination and the collected ante-mortem data.

For security reasons, Bergonio said the SOCO-Disaster Victim Identification could not conduct a full operation on the retrieved bodies yet since the unit is still waiting to be cleared by the AFP allowing it to freely go around Marawi.

For now, all 57 collected antemortem and postmortem data are preserved at the DNA lab inside Camp Crame.

Violence erupted in May after local Islamic State-inspired extremists laid siege in the southern Islamic city.

The clashes prompted President Rodrigo Duterte to place the entire Mindanao region under martial rule.

As of August 10, fighting in Marawi has killed 128 government fighters and 45 civilians. 552 enemies have also been killed.

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45 bodies recovered from Marawi up for DNA tests: PNP - ABS-CBN News

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Genome sequencing method can detect clinically relevant mutations using five CTCs – Medical Xpress

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August 15, 2017

Whole genome sequencing using long fragment read (LFR), a technology that can analyze the entire genomic content of small numbers of cells, detected potentially targetable mutations using only five circulating tumor cells (CTCs) in a patient with metastatic breast cancer.

The study is published in Cancer Research, a journal of the American Association for Cancer Research, by Brock Peters, PhD, senior director of research at Complete Genomics Inc. in San Jose, California, and BGI-Shenzhen in Shenzhen, China; John W. Park, MD, professor of clinical medicine, and director of Novel Therapeutics, Breast Oncology, at University of California, San Francisco (UCSF); Hope S. Rugo, MD, professor of medicine and director of breast oncology and clinical trials education at UCSF.

The Complete Genomics team and colleagues from UCSF evaluated CTCs from two liquid biopsies drawn from a 61-year-old female patient with ER-positive/HER2-negative metastatic breast cancer at two different time points during her course of treatment. First, they isolated 34 highly pure CTCs using immunomagnetic enrichment/fluorescence-activated cell sorting (IE/FACS) technology developed by Park and Mark Magbanua, PhD, at UCSF. Then they used LFR to perform advanced whole-genome sequencing by splitting the genomic DNA from the CTCs into 3,072 individual compartments, with each compartment containing approximately 5 percent of the cancer genome. The DNA in each compartment was subsequently labeled with a unique barcode, the compartments were combined, and the genomic DNA and barcodes were sequenced.

"From 34 cells we accurately detected mutations present in as few as 12 percent of CTCs, established the tissue of origin, and identified potential personalized combination therapies for this patient's highly heterogeneous disease," said Peters.

According to Peters, this research is the first application of LFR technology to CTCs. "LFR subdivides the genome into compartments, allowing us to count the fragments with somatic mutations across all the compartments to accurately quantify the number of mutations present in a population of cells. It also serves to remove false-positive single nucleotide variants," explained Peters.

"LFR, which explores the more than 20,000 genes in the genome and all non-coding regions, is more comprehensive than gene panels, which examine about 100 genes and focus on small genomic regions typically associated with a disease," he continued.

Because prior studies indicate that five CTCs can be expected in about half of the patients with metastatic disease, and evaluating 34 CTCs is cost-prohibitive, Peters and colleagues analyzed five different batches of five CTCs and replicated their findings. The researchers estimated that the cost of their advanced whole genome sequencing technique on five CTCs would be about $3,000 within the next few years, in line with current oncology diagnostic tests.

"That our sequencing method could detect the most important somatic mutations from just five CTCs in a noninvasive liquid biopsy is important, demonstrating cost-effectiveness and utility in clinical settings," said Peters.

"Our work highlights the importance and utility of using accurate and quantitative whole genome analysis in a clinical setting," said Peters. "We identified targetable mutations that would have been missed by current clinical sequencing strategies. In the near precision medicine future, this type of information will be critical for selecting effective personalized multi-drug treatments."

Study co-author John W. Park, MD, professor of clinical medicine, and director of Novel Therapeutics, Breast Oncology, at University of California, San Francisco (UCSF), said, "We observed that it is possible to develop a robust strategy for liquid biopsy using whole genome sequencing of circulating tumor cells. This approach allows detailed molecular profiling across the patient's entire cancer genome."

Study co-author, Hope S. Rugo, MD, professor of medicine and director of breast oncology and clinical trials education at UCSF, said, "The IE/FACS allows for exquisite and full-scale isolation of highly pure CTCs with little or no contamination of normal blood cells, thus providing the robustness needed for accurate whole genome sequencing of a few cells. Taken together, the liquid biopsy platform we described in this study suggests a viable approach for minimally invasive yet comprehensive and real-time testing of metastatic cancer in the clinic."

According to Peters, the main limitations to the study are that only a single patient was studied and none of the suggested possible therapies could actually be tested, emphasizing the need for larger studies.

Explore further: Researchers working on blood test to detect brain metastases while still treatable

As the field of liquid biopsies for tracking disease progression and therapeutic response heats up, many doctors are looking for ways to apply this approach to their patients. Currently, assays for circulating tumor cells ...

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Genome sequencing method can detect clinically relevant mutations using five CTCs - Medical Xpress

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Human intrusion on fruit bat habitats raises exposure risk to Hendra virus in Australia – Phys.Org

Posted: at 11:46 am

August 15, 2017 Black flying fox (Pteropus alecto). Credit: James Nilson

There is a rising risk of human and domestic animal exposure to deadly Hendra virus (HeV) carried by fruit bats in Eastern Australia due to human intrusion into their habitats, human proximity to woodlands and vegetation loss, a new study reveals.

Reported today in Scientific Reports by researchers from the University of Sydney, University of Melbourne and State University of New York, the study traces how pressures such as expanding human populations, urbanisation and forest fragmentation altered the shape and size of the habitats of pteropid fruit bats (flying foxes) in the decades between 1980 and 2015.

In recent years, bats from the Pteropodidae family have been pinpointed as 'natural reservoirs' of several emerging zoonotic viruses, such as Hendra virus (HeV), Nipah (NiV) and Ebola, which can cause death in humans.

Pteropid fruit bats carry HeV without becoming ill. Research has shown the black flying fox (Pteropus alecto) and the spectacled flying fox (Pteropus conspicillatus) harbor the infectious HeV and can shed HeV particles in their urine.

Their suitability as reservoirs has been linked to their capacity for flight, adaptability to different food sources, population structure, longevity and immune function.

"Pteropid fruit bats are essential pollinators and seed distributors in tropical and subtropical forests," says Dr Michael Walsh of the University of Sydney's Marie Bashir Institute for Infectious Diseases and Biosecurity, who led the study.

"Human-caused changes in their habitat exemplify the precarious balance between ecosystem integrity and human public health.

"The opportunity for the transmission of animal-borne viruses to human populations arises when these changes in natural habitats create new configurations of ecosystems and animal populations that subsequently generate increased or unprecedented contact between human, domestic animal and wildlife communities."

Hendra virus was first identified during the first recorded outbreak of the disease in the Brisbane suburb of Hendra, Australia, in 1994. The outbreak involved 21 stabled racehorses and two human cases.

This newly emerging infectious disease made several further sporadic occurrences between 1994 and 2010 until in 2011 an unprecedented number of 18 distinct 'spillovers' more than doubled the number of known incidents.

A spillover event is defined as transmission of a pathogen such as HeV from a reservoir such as such as a pteropid fruit bat to a domestic animal such as a horse. It also includes pathogen transmission from an infected domestic animal such as a horse to a human.

As of August 2017, there have been 60 known outbreaks of Hendra resulting in the death of 102 horses, all occurring in the north-eastern coastal region of Australia.

To date, seven humans have contracted HeV in spillover events arising from the care or autopsy of ill or dead horses. Of those who tested positive for HeV, four died of the disease, including two veterinarians.

"The epidemiology of HeV spillover events indicates that expanding suburban communities may draw foraging flying foxes from nearby forest ranges into encroaching residential and community gardens and thereby, closer to horses," Dr Walsh says.

The researchers did two sets of analyses to assess whether an expansion of the HeV reservoir was associated with an increasing trend in spillover risk.

First, they modeled changes in 1713 geo-located sightings of pteropid fruit bats P. alecto and P. conspicillatus at three different time points between 1980 and 2015 in response to factors such as climate, topography, and human migration in the preceding decade.

They found that rainfall, altitude, temperature, and human migration were highly associated with decadal changes in the ecological niche (as measured by sightings) of the black flying fox and the spectacled flying fox.

"The predicted habitat suitability for HeV reservoir pteropids expands geographically southward along the eastern coast of Australia from the earliest period in 1980-1989 to the latest in 2000-2015," Dr Walsh says.

"These changes predict that southeastern Queensland and northeastern NSW show consistently high habitat suitability, while advancing toward and beyond Sydney. There is also a corridor along the northern coast of the Northern Territory that shows a high degree of predicted habitat suitability."

In their second analysis, the researchers assessed whether HeV infections in horses and humans (spillover incidents) between 2000 and 2015 were associated with decadal changes in the ecological niche (as measured by sightings) of P. alecto and P. conspicillatus from 1980 to 2015.

They found a high association between the two, meaning the inter-decadal expanding reservoir niche of pteropid fruit bats was highly associated with a concurrent increasing trend for risk of HeV infections in humans.

Furthermore, the risk of HeV infection increased threefold as the ecological niche expanded along the coast in Queensland and NSW during the first two decades under study (1980-1999) and increased further still as habitat suitability continued to change from 2000-2015.

"The shared history between HeV spillover and the ecological niche of flying foxes notwithstanding, reservoir habitat suitability alone was insufficient to describe the spatial dependence of HeV spillover," says Dr Walsh.

"The human footprint, proximity to woody savanna, and vegetation loss were additional components of the landscape required to adequately describe the spatial dependence of spillover across eastern Australia."

The findings supported the researchers' hypothesis that the risk for HeV infection in Eastern Australia between 2000 and 2015 was associated with changes in the ecological niche of pteropid fruit bats in the decades between 1980 and 2015.

Furthermore, this risk was highly associated with human intrusion into their habitats, human proximity to woodlands and vegetation loss.

Explore further: Killer horse virus spreads in Australia

Australian officials were on Saturday working to isolate potential victims after uncovering two more cases of the deadly horse-borne Hendra virus, which has erupted in a second state.

A horse was put down in Australia after contracting the deadly Hendra virus -- the ninth animal to die in an outbreak which has exposed almost 50 people in two states.

Another six people have been tested for the deadly Hendra virus after it claimed the life of a seventh horse, officials said Thursday, as the killer outbreak spread south.

An experimental drug so far only tested on animals has been given to an Australian woman and child in an effort to prevent an outbreak of a potentially deadly virus, health officials said Tuesday.

Concern over the killer Hendra virus mounted in Australia Wednesday after a sixth horse died in an outbreak, and 26 people underwent tests after coming into contact with sick animals.

An invisible barrier separates land animals in Australia from those in south-east Asia may also restrict the spillover of animal-borne diseases like avian flu, but researchers have found that fruit bats on either side of ...

Color in the plant kingdom is not merely a joy to the eye. Colored pigments attract pollinating insects, they protect plants against disease, and they confer health benefits and are used in the food and drug industries. A ...

A new study describes how head-on collisions between protein machines on chromosomes can disrupt DNA replication and boost the rate of gene mutations that help bacteria survive hostile environments, resist antibiotics, and ...

There is a rising risk of human and domestic animal exposure to deadly Hendra virus (HeV) carried by fruit bats in Eastern Australia due to human intrusion into their habitats, human proximity to woodlands and vegetation ...

Centuries ago, the ancient networks of the Silk Road facilitated a political and economic openness between the nations of Eurasia. But this network also opened pathways for genetic exchange that shaped one of the world's ...

Chromatin remodelersprotein machines that pack and unpack chromatin, the tightly wound DNA-protein complex in cell nucleiare essential and powerful regulators for critical cellular processes, such as replication, recombination ...

The emergence in recent years of the first mammalian haploid cell lines has raised great expectations in the scientific community. Despite their potential, these cultures present some issues that complicate their use because ...

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Human intrusion on fruit bat habitats raises exposure risk to Hendra virus in Australia - Phys.Org

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Genomic Medicine Has Entered the Building – Hospitals & Health Networks

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Hospitals & Health Networks
Genomic Medicine Has Entered the Building
Hospitals & Health Networks
In July, the group published a report in the New England Journal of Medicine describing a variant of the gene ANGPTL3 associated with a reduced risk of cardiovascular disease detected in some MyCode participants. The gene variant codes for a protein ...

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Gene-editing scientists to share $500K Albany Med prize – Albany Times Union

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Jennifer Doudna, Ph.D. , professor, Molecular and Cell Biology and Chemistry, University of California, Berkeley. (UC-Berkeley)

Jennifer Doudna, Ph.D. , professor, Molecular and Cell Biology and Chemistry, University of California, Berkeley. (UC-Berkeley)

Luciano Marraffini, Ph.D., associate professor, Laboratory of Bacteriology, The Rockefeller University, New York City. (Mario Morgado)

Luciano Marraffini, Ph.D., associate professor, Laboratory of Bacteriology, The Rockefeller University, New York City. (Mario Morgado)

Gene-editing scientists to share $500K Albany Med prize

Albany

Five scientists whose work on the revolutionary gene-editing technology CRISPR will share the 2017 Albany Medical Center Prize in Medicine and Biomedical Research.

The decision by the Albany Prize National Selection Committee to award the $500,000 prize to these researchers stands out from recent announcements of the prestigious award, which have acknowledged scientists for groundbreaking work leading to current medical advances. While developments using CRISPR have exploded this year, its use in humans remains a promise, but one with far-reaching effects.

"The committee saw this technology as having huge potential for eradicating human disease," said Dr. Vincent Verdile, dean of Albany Medical College and chair of the prize committee.

CRISPR (pronounced "crisper") stands for "clustered regularly interspaced short palindromic repeats." It is a DNA sequence that simple bacteria use to defend themselves against viruses by snipping out part of the virus DNA so it can be recognized by the bacteria's own immune systems. The technology based on it lets scientists "edit" genes at specific locations by removing, adding or altering parts of the DNA sequence.

In the last year, CRISPR technology has been used to remove a gene linked to heart disease from human embryos and to create a cancer-killing gene that shrinks tumors in mice. Last week, scientists revealed in the journal Science that they had created piglets stripped of viruses that could cause disease in humans; the technique could open the door for eventual transplantation of livers, hearts and other organs from pigs to people.

The scientists who will share the Albany Prize are:

Emmanuelle Charpentier of the Max Planck Institute for Infection Biology in Germany. Charpentier is co-inventor and co-owner of the intellectual property comprising the CRISPR gene-editing system, and co-founder of two companies developing the technology for biotech and biomedical applications.

Jennifer Doudna of the University of California, Berkeley. Five years ago, Doudna described a simple way of editing the DNA of any organism using an RNA-guided protein founded in bacteria.

Luciano Marraffini of Rockefeller University in New York City. Marraffini discovered that CRISPR works by severing DNA and was the first to propose that it could be used to edit genes in organisms other than bacteria. With Feng Zhang, he performed the first successful CRISPR gene-editing experiment in human cells.

Francisco J.M. Mojica of the University of Alicante in Spain. Mojica's work has led to the development of tools used in the genetic manipulation of any living being, including humans.

Feng Zhang of the Broad Institute of Massachusetts Institute of Technology and Harvard University. Zhang pioneered the development of gene editing tools for use in human cells from bacterial CRISPR systems.

The Albany Prize Committee's selection of five scientists to share the award this year reflects an increasing trend in science toward collaboration, where information is shared and groups of researchers move knowledge forward in ways that no one of them could do alone, Verdile said. It's a major change since the days when a single scientist would be credited with, say, the discovery of a vaccine.

"That's more of where the future of biomedical research is going what's good for the good of mankind, not me personally," Verdile said.

News reports in recent years have focused on the ethical aspects of CRISPR technology, which in addition to its potential to prevent devastating diseases, could also be used for cosmetic purposes or have unintended consequences that affect the descendants of the person whose genes are edited. The Albany Prize Committee did not consider such "what if" scenarios, Verdile said, leaving those conversations for future ethicists and policymakers as specific medical techniques are developed.

The Albany Prize, one of the nation's largest for science and medicine, was established in 2000 by the late Morris "Marty" Silverman, a New York City businessman and philanthropist who grew up in Troy. A commitment of $50 million from the Marty and Dorothy Silverman Foundation allows for the prize to be awarded annually for 100 years.

Albany Med released the 2017 award recipients' names Tuesday morning. The recipients will formally receive their awards at a Sept. 27 ceremony in Albany.

chughes@timesunion.com 518-454-5417 @hughesclaire

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Gene-editing scientists to share $500K Albany Med prize - Albany Times Union

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New Hampshire biologist reacts to gene-editing discovery – The Union Leader

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By KIMBERLY HOUGHTON Union Leader Correspondent August 14. 2017 11:06PM

This sequence of images shows the development of embryos after being injected with a biological kit to edit their DNA, removing a genetic mutation known to cause hypertrophic cardiomyopathy.(Oregon Health & Science University)

Bryan Luikart, an associate professor of molecular and systems biology at Geisel School of Medicine at Dartmouth College.

It is pretty amazing. It is a super-exciting time to be a scientist right now, said Bryan Luikart, an associate professor of molecular and systems biology at Geisel School of Medicine at Dartmouth College.

The study, which was published in the journal Nature, was detailed in a New York Times report. According to the article, Oregon researchers reported they repaired dozens of human embryos, fixing a mutation that causes a common heart condition that can lead to sudden death later in life.

The way they have dodged some ethical considerations is that they didnt go on to have that embryo grow into a person, said Luikart, explaining that if the embryos with the repaired mutation did have the opportunity to develop, they would be free of the heart condition.

At the Geisel School of Medicine at Dartmouth, Luikart and his colleagues have already been using this concept with mouse embryos, focusing specifically on autism.

Researchers are using the gene-editing method called CRISPR-Cas9 in hopes of trying to more fully understand autism, which he said is the most critical step in eventually finding a cure.

I think the CRISPR is a tremendous breakthrough. The question really is where and when do you want to use it, Luikart said. I have no ethical concerns using it as a tool to better understand biology.

The new milestone, an example of human genetic engineering, does carry ethical concerns that Luikart said will trigger some debates. He acknowledged that while the advancement of gene-editing technology could eventually stop unwanted hereditary conditions, it also allows for creating babies with smarter, stronger or more attractive traits.

The ability to do that is now within our grasp more than it has ever been, he said.

More importantly, the breakthrough could ultimately eliminate diseases, Luikart said. As the technology advances, he said, genetic diseases that are passed down to children may be corrected before the child receives them.

He used another example of a brain tumor, which often returns after it is surgically removed. Now, once the brain tumor is removed, there is the possibility of placing something in the space to edit and fix the mutation that causes the brain tumor in the first place if physicians are able to find the right cell to edit, Luikart said.

People are definitely thinking along those lines, or cutting the HIV genome, said Luikart, who predicts that those advancements will occur in mice within the next decade, and the ability to do that in humans is definitely there.

The big question is whether that can occur without some sort of side effect that was not predicted, he said.

Columbia University Medical Center posted an article earlier this year warning that CRISPR gene editing can cause hundreds of unintended mutations, based on a study published recently in Nature Methods.

This past May, MilliporeSigma announced it has developed a new genome editing tool that makes CRISPR more efficient, flexible and specific, giving researchers more experimental options and faster results that can accelerate drug development and access to new therapies, according to a release.

CRISPR genome editing technology is advancing treatment options for some of the toughest medical conditions faced today, including chronic illnesses and cancers for which there are limited or no treatment options, states the release, adding the applications of CRISPR are far ranging from identifying genes associated with cancer to reversing mutations that cause blindness.

It is pretty big news, Luikart said.

khoughton@newstote.com

Health Hanover

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New Hampshire biologist reacts to gene-editing discovery - The Union Leader

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A New Gene Editing Technique Could Finally Allow Us to Treat ALS – Futurism

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In BriefResearchers from UC San Diego's School of Medicine have testeda modified CRISPR-Cas9 technique designed to target RNA instead ofDNA. Rcas9 could potentially improve the lives of patients withALS, Huntington's disease, or myotonic dystrophy by delaying theprogression of their disorders. Editing RNA

The most efficient and effective gene-editing tool in use today is CRISPR-Cas9. Just this year, researchers have successfully used it fora wide variety of experiments, from modifying garden vegetables to encoding a GIF in bacterial DNA. Most recently, the tool was used to remove a genetic disease from a human embryo.

Although undeniably powerful, CRISPR-Cas9 does have its limitations; it can only target DNA. To extend its capabilities to includeRNA editing, researchers from the University of California San Diego (UCSD) School of Medicinedeveloped amodification of CRISPR, and theyre calling their toolRNA-targeting Cas9 (RCas9).

In a study published in Cell, the UCSD team tested their technique by correcting the kinds of molecular mistakes that cause people to develop microsatellite repeat expansion diseases, such ashereditary amyotrophic lateral sclerosis (ALS)and Huntingtons disease.

During standard CRISPR-CAs9 gene editing, a guide RNA is instructed to deliver a Cas9 enzyme to a specific DNA molecule. The researchers from UCSD instead instructed it to target an RNA molecule.

Tests conducted in the laboratory showed that RCas9 removed 95 percent ofproblem-causing RNA for myotonic dystrophy types 1 and 2, Huntingtons disease, and one type of ALS. The technique also reversed 93 percent of the dysfunctional RNA targets in the muscle cells of patients with myotonic dystrophy type 1, resulting in healthier cells.

This is exciting because were not only targeting the root cause of diseases for which there are no current therapies to delay progression, but weve re-engineered the CRISPR-Cas9 system in a way thats feasible to deliver it to specific tissues via a viral vector, senior author Gene Yeo, a cellular and molecular medicine professor at UCSD School of Medicine, explained in a press release.

Across the globe, an estimated 450,000 patients are said to be living with ALS. Roughly 30,000 of those are from the U.S. where 5,600 people are diagnosed with the diseases every year. The exact number of Huntingtons disease cases, however, isnt quite as easy to pin down. One estimate says that around 30,000 Americans display symptoms of it, while more than 200,000 are at risk.

Regardless of the exact numbers, these two neurological diseases clearly affect a significant number of people. This prevalence and the absence of a known curemakes the UCSD teams research all the more relevant. Even more exciting is the fact that the same kinds of RNA mutations targeted by this study are known to cause more than 20 other genetic diseases.

Our ability to program the RCas9 system to target different repeats, combined with low risk of off-target effects, is its major strength, co-first author of the study Ranjan Batra said in the UCSD press release.

However, the researchers do know that what theyve accomplished is just a first step. While RCas9 works in a lab, they still have to figure out how it will fare when tested in actual patients.

The main thing we dont know yet is whether or not the viral vectors that deliver RCas9 to cells would elicit an immune response, explained Yeo. Before this could be tested in humans, we would need to test it in animal models, determine potential toxicities, and evaluate long-term exposure.

Ultimately, while RCas9 couldnt exactly deliver a cure, it could potentially extend patients healthy years. For disease like ALS and Huntingtons, thats a good place to start.

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Gene Editing System Revamped to Target RNA Aggregates Found in Inherited ALS – ALS News Today

Posted: at 11:45 am

Researchers have found a way to break down aggregated RNA molecules that cause diseases such as certain inherited forms of amyotrophic lateral sclerosis (ALS).

As the technique has the potential to treat several diseases which currently lack treatment options, the research team from theUniversity of California, San Diego (UCSD) made sure to engineer the new system so that it could be delivered to specific tissues with non-infectious viruses.

The method builds on a well-known gene-editing system, called CRISPRCas9, but was adapted to target RNA instead of DNA. The new method is called RNA-targeting Cas9, or simply, RCas9.

This is exciting because were not only targeting the root cause of diseases for which there are no current therapies to delay progression, but weve re-engineered the CRISPR-Cas9 system in a way thats feasible to deliver it to specific tissues via a viral vector, the studys senior author, Gene Yeo, said in a press release. He is aprofessor of cellular and molecular medicine at UCSD School of Medicine.

The study, Elimination of Toxic Microsatellite Repeat Expansion RNA by RNA-Targeting Cas9, published in the journal Cell, described how the team rebuilt the Cas9 system to find and chop up disease-causing RNA molecules.

In gene editing, the CRISPRCas 9 system uses an RNA probe that matches a specific stretch of DNA. Once bound to the right gene, the Cas9 enzyme cuts the DNA, which then can be inactivated or edited. The new system targets RNA, and chops it upinstead of editing it.

RNA, whichis largely composed of similar building blocks as DNA, has numerous roles in a cell. For instance, it is used to take a copy of a gene to provide instructions for the cells protein-making machinery.

At times, however, RNA molecules start accumulating what researchers call microsatellite repeat expansions. These are stretches of repeat RNA letters that disrupt the normal activity of the RNA. When found in messenger RNAs, they prevent necessary proteins from being made.

Anabnormal sequence also makes the RNA accumulate in cells, disrupting other cell operations. This can be seen in ALS that runs in families, andin diseases such as myotonic dystrophy and Huntingtons.

In ALS, such repeats are found in the C9orf72 gene, and cause about a third of familial ALS cases, or those that run in families,according to the ALS Association.

Testing the new tool in lab-grown cells derived from ALS patients with such mutations, the team showed that RCas9 could eliminate at least 95 percent of accumulated RNA, seen as dense clusters, or foci, in the cells.

They also discovered that using RCas9 freed proteins that normally bind to RNA in cells. When abnormal RNA starts accumulating in a cell, these proteins get tied up interacting with the aggregates, instead of binding to their natural targets. Researchers said that treated patient-derived cells eventually resembled healthy cells.

For the system to be useful as a human therapy, it needs to fit into a virus the most common way to deliver gene therapy. Normal Cas9 is too large to fit into thevirus typically used. The team solved the issue by removing parts of the Cas9 enzyme required for cutting DNA, making the enzyme small enough to fit.

Yet, many more questions need to be answered before the method can be tried in patients.

The main thing we dont know yet is whether or not the viral vectors that deliver RCas9 to cells would elicit an immune response, Yeo said. Before this could be tested in humans, we would need to test it in animal models, determine potential toxicities and evaluate long-term exposure.

The group has launched a company, Locana, that will work onpreclinical-trial development of the method with the aim of bringing it to patients.

We are really excited about this work because we not only defined a new potential therapeutic mechanism for CRISPR-Cas9, we demonstrated how it could be used to treat an entire class of conditions for which there are no successful treatment options, said David Nelles, PhD, one of two lead studyauthors.

There are more than 20 genetic diseases caused by microsatellite expansions in different places in the genome. Our ability to program the RCas9 system to target different repeats, combined with low risk of off-target effects, is its major strength, added Ranjan Batra, PhD, the studys other lead author.

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Benedict Cumberbatch as Nigel Farage? Hollywood Plans TV Adaptation of Pro-Trump Brexit Book – Newsweek

Posted: at 11:45 am

Britains Brexit process has got all the ingredients of a white-knuckle Hollywood blockbuster: colorful characters; the fate of a nation at stake; lengthy negotiations over minor changes to customs regulations.

So its perhaps no surprise that a major Hollywood studio plans to sign the rights to a book on last years EU referendum, according to The Daily Telegraph. Benedict Cumberbatch of Sherlock fame could even be considered to play Nigel Farage.

The paper reports that the script for the 60 million ($78 million) project is nearly finished and that shooting is planned to start in the new year. The six-part series would be based on a book, The Bad Boys of Brexit, by Arron Banks, who ran Leave.EU, an unofficial pro-Brexit campaign, during the referendum.

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Casting will take place in the Autumn and Cumberbatch is among the names mentioned in the media in relation to the project.

Aside from Farage, other main characters in the book include the American pollster Gerry Gunster and Banks himself. The film will reportedly be told from Gunsters perspective.

Donald Trump even makes an appearance; Banks and Farage met the president during a post-referendum visit to the U.S. and were later pictured with him in front of a golden elevator in Trump tower.

A source told the Telegraph that it would be an against all odds story in which a respected U.S. expert has to control these British lunatics.

Banks and Farage both cultivate a maverick, politically incorrect public image and rely on controversy to stir up publicity. In recent weeks, Bankss Leave.EU provoked outrage when it responded to news that Gina Miller, a pro-EU campaigner, had been threatened with acid attacks by political opponents. Leave.EU tweeted a gif suggesting she should leave the U.K., with the caption theres the door, liberals.

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