Gene-editing damages DNA more than thought: study

Agencies
July 17, 2018

Paris, Jul 17:  A revolutionary gene editing technique hailed as the future of disease eradication and mooted for a Nobel Prize may be less precise and cause more cell damage than previously thought, researchers said Monday.

Lab experiments using mouse and human cells revealed that the CRISPR-Cas9 technique "frequently" caused "extensive" gene mutations, a study team reported.

"This is the first systematic assessment of unexpected events resulting from CRISPR-Cas9 editing," said Allan Bradley of the Wellcome Sanger Institute in England, where the team conducts research.

The research showed that "changes in the DNA have been seriously underestimated before now," said Bradley, who co-authored a study published in the journal Nature Biotechnology.

The mutations have not been shown to be harmful, nor benign.

"It is important that anyone thinking of using this technology for gene therapy proceeds with caution and looks very carefully to check for harmful effects," Bradley said in a statement issued by the institute.

First unveiled about six years ago, CRISPR-Cas9 allows scientists to insert, remove and correct a faulty sequence on a strand of DNA in a cell with pinpoint precision.

It has raised hopes that one-day disease-causing genes could be removed or altered before a baby is even born.

In recent years, CRISPR-Cas9 has repeatedly been predicted to win the Nobel Chemistry Prize.

CRISPRs -- clustered regularly interspaced short palindromic repeats -- are part of the immune defence system in bacteria, used to hone in on the exact spot on the genome where the cut should be made.

Cas9 is a protein used as "scissors" to snip through the faulty gene, which is then replaced or fixed by the cell's own DNA repair mechanism.

The technique's safety has not yet been proven, and it is not approved for use in human therapy.

So far, researchers have used it to improve hearing in mice going deaf and to fix a disease-causing mutation in cloned, early-stage human embryos.

But the new finding raises "safety implications," the team said.

They found "large genetic rearrangements such as DNA deletions and insertions" in cells, which could lead to important genes being switched on or off and causing dangerous changes.

The research also showed that standardized tests do not pick up damage to DNA caused by CRISPR-Cas9.

Experts not involved in the study said it was unclear how such large, unintended changes were not noticed before.

But, "the results give no reason to panic or to lose faith in the methods when they are carried out by those who know what they are doing," said Robin Lovell-Badge of The Francis Crick Institute, a biomedical research centre in London.

For Francesca Forzano, a consultant in clinical genetics and genomics with the Guy's and St Thomas' NHS Foundation Trust, the work showed that CRISPR-Cas9 "is much less safe than previously thought" and that safety-monitoring techniques were "not entirely adequate".

More research is needed before any clinical application of the method is considered, said Forzano.

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News Network
July 9,2020

Washington, Jul 9: Ayurvedic practitioners and researchers in India and the US are planning to initiate joint clinical trials for Ayurveda formulations against the novel coronavirus, the Indian envoy here has said.

In a virtual interaction with a group of eminent Indian-American scientists, academicians, and doctors on Wednesday, Indian Ambassador to the US Taranjit Singh Sandhu said the vast network of institutional engagements have brought scientific communities between the two countries together in the fight against Covid-19.

 “Our Institutions have also been collaborating to promote Ayurveda through joint research, teaching and training programs. Ayurvedic practitioners and researchers in both the countries are planning to initiate joint clinical trials of Ayurvedic formulations against Covid-19,” Sandhu said.

“Our scientists have been exchanging knowledge and research resources on this front,” he said.

The Indo-US Science Technology Forum (IUSSTF) has always been instrumental in promoting excellence in science, technology, and innovation through collaborative activities.

To address Covid-19-related challenges, the IUSSTF had given a call to support joint research and start-up engagements. A large number of proposals are being reviewed on fast track mode by the experts on both the sides, he said.

“Indian pharmaceutical companies are global leaders in producing affordable low-cost medicines and vaccines and will play an important role in the fight against this pandemic,” Sandhu said.

According to the ambassador, there are at least three ongoing collaborations between Indian vaccine companies with US-based institutions.

These collaborations would be beneficial not just to India and the US, but also for the billions who would need to be vaccinated against Covid-19 across the world, he noted.

Asserting that innovation will be the key driver in pandemic response and recovery, he said tech-companies and start-ups have already begun to take the lead in this direction.

"Telemedicine and telehealth will evolve as will other digital platforms across sectors," he said.

Noting that there has been a longstanding collaboration between India and the US in the health sector, he said scientists have been working together in several programs to understand important diseases at the basic and clinical level.

Many such programs have been focused on translational research to develop new therapeutics and diagnostics.

There are over 200 ongoing NIH funded projects in India involving 20 institutions from NIH network and several eminent institutions in India engaged in a wide spectrum of research areas to create health care solutions, the senior diplomat said.

The collaboration under Vaccine Action Program (VAP) resulted in the development of ROTAVAC vaccine against rotavirus which causes severe diarrhea in children.

The vaccine was developed by an Indian company (Bharat Biotech) at an affordable cost. It has been commercialised and introduced in the Expanded Program on Immunisation.

Development of many other vaccines such as TB, Influenza, Chikungunya are also in progress under the VAP, he said.

 “As I speak, the VAP meeting is in progress where experts from both countries are deeply engaged in technical discussions to expedite development of Covid-19 vaccine,” Sandhu said in his remarks.

During the interaction, the eminent experts appreciated India's handling of the Covid-19 pandemic and offered their valuable suggestions and best practices in this regard.

They shared their ideas on deepening the knowledge partnership between India and the US.

The experts who took part in the interaction, were drawn from wide-ranging fields including artificial intelligence, quantum information science, biomedical engineering, robotics, mechanical engineering, earth and ocean science, virology, physics, astrophysics, and health sciences.

Prominent among those who attended the virtual interaction were Subhash Kak Regents Professor at Oklahoma State University, Dr Vijay Kuchroo, Samuel L Wasserstrom Professor of Neurology at Harvard Medical School, Dr Ashish M Kamat, Professor of Urology at MD Anderson Cancer Center, Ashutosh Chilkoti, Alan L Kaganov Professor of Biomedical Engineering and Chair of the Department of Biomedical Engineering at Duke University; and Prof Manu Prakash, a professor in Department of Bioengineering at Sandford University, among others.

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Agencies
May 17,2020

Geneva, May 17: Spraying disinfectant on the streets, as practised in some countries, does not eliminate the new coronavirus and even poses a health risk, the World Health Organization (WHO) warned on Saturday.

In a document on cleaning and disinfecting surfaces as part of the response to the virus, the WHO says spraying can be ineffective. "Spraying or fumigation of outdoor spaces, such as streets or marketplaces, is... not recommended to kill the Covid-19 virus or other pathogens because disinfectant is inactivated by dirt and debris," explains the WHO.

"Even in the absence of organic matter, chemical spraying is unlikely to adequately cover all surfaces for the duration of the required contact time needed to inactivate pathogens." The WHO said that streets and pavements are not considered as "reservoirs of infection" of Covid-19, adding that spraying disinfectants, even outside, can be "dangerous for human health".

The document also stresses that spraying individuals with disinfectants is "not recommended under any circumstances".

"This could be physically and psychologically harmful and would not reduce an infected person's ability to spread the virus through droplets or contact," said the document.

Spraying chlorine or other toxic chemicals on people can cause eye and skin irritation, bronchospasm and gastrointestinal effects, it adds.

The organisation is also warning against the systematic spraying and fumigating of disinfectants on to surfaces in indoor spaces, citing a study that has shown it to be ineffective outside direct spraying areas.

"If disinfectants are to be applied, this should be done with a cloth or wipe that has been soaked in disinfectant," it says.

The SARS-CoV-2 virus, the cause of the pandemic that has killed more than 300,000 people worldwide since its appearance in late December in China, can attach itself to surfaces and objects.

However, no precise information is currently available for the period during which the viruses remain infectious on the various surfaces.

Studies have shown that the virus can stay on several types of surfaces for several days. However, these maximum durations are only theoretical because they are recorded under laboratory conditions and should be "interpreted with caution" in the real-world environment.

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Agencies
April 15,2020

Dear parents, if you want your children to have proper sleep, read this carefully. Joining a growing list of studies that tell parents to shun devices at bed-time, researchers say that children who use devices and decide what time they go to sleep, achieve less sleep and feel more sleepier the following day than their peers.

The study of children in this age-group (aged 11 to 13 years), published in the New Zealand Medical Journal, found most (72 per cent) of the 163 students interviewed by University of Otago researchers achieved recommended guidelines of an average 9 to 11 hours sleep nightly over one week.

"But that also means that almost one in four students did not achieve sleep within these guidelines, which highlights an area for improvement," said study researcher Kate Ford.

However, consistent with previous research in 15 to 17-year-old New Zealanders, the study results show less sleep on the nights where devices are used in the hour before bed.

According to the researchers, students who used devices before going to sleep were also more likely to report that they felt sleepy the following morning. Watching television before bed had no significant effect on sleep length.

There were also some interesting observations over the weekends where students went to bed later but woke later achieving similar sleep length to the school days, the researchers said.

A small group of students (six per cent) who reported less than seven hours of sleep, including a small number reporting not sleeping at all, according to the study,

Therefore, while the average across the week of 72 per cent of students reporting adequate sleep is reassuring, it is far from the goal of every child achieving sleep within the recommended guidelines," Ford said.

Dr Paul Kelly, head of the Sleep Health Service at Canterbury District Health Board, supervised the study and explained that the foundations for good health are based on proper nutrition, regular exercise and good sleep quality.

Sleep quality is often overlooked as a contributory factor to poor health.

"The study findings suggest the need for parental guidance around bedtimings and moderation of the use and availability of electronic devices before bed," Kelly said.

"Respect and protect your sleep, as good daytime functioning is reliant on adequate sleep," Kelly added.

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