Gene editing allows scientists to modify sections of an organism’s DNA and is considered a promising treatment for a number of genetic diseases. There have been numerous advances in the laboratory over the last few decades, but there are still many challenges to overcome before gene editing can be widely used in the patient population. Launched in 2018, the Somatic Cell Gene Editing Consortium (SCGE) has brought together some of the leading researchers in the field to advance discovery and accelerate the translation of somatic gene editing advances in the lab to the clinical setting.

Over six years, the NIH will allocate approximately $190 million to SCGE to realize gene editing’s potential. The end result will be a freely available toolkit that will provide the biomedical research community with rigorously evaluated information about genome editors and methods for delivering and tracking gene editing molecules.

“NIH realized it was important for all of us who are investigating gene editing to work together toward a common goal,” said Carnegie Mellon University Professor of Chemistry Danith Ly who joined the consortium in 2019. “We’re designing molecules that can go into the cell and we’re cataloging each and every one. What we’ll end up with is a very valuable, rigorously evaluated resource for those who want to bring gene editing to patients.”

While much of the consortium’s work focuses on CRISPER-Cas related systems, the SCGE points out that it’s important to continue to develop other systems. They specifically single out the peptide nucleic acid-based gene editing technique developed by Carnegie Mellon’s Ly and Yale University’s Peter Glazer.

“Although there is a significant focus on CRISPR-Cas related systems within the SCGE, it is crucial to continue to explore alternate systems, in part because they may differ in both their potential for delivery and their biological or immunological responses,” the consortium wrote in Nature.

While CRISPR-Cas edits genes in cells that have been removed from the body, Ly and Glazer’s peptide nucleic acid (PNA) system is administered intravenously and edits cells in vivo. Using nanoparticles, a PNA molecule paired with a donor strand of DNA is delivered directly to a malfunctioning gene. Ly, a leading researcher in synthetic nucleic acid technology, has programmed PNA molecules to open double stranded DNA at the site of a targeted mutation. The donor DNA from the complex binds to the cell’s faulty DNA and triggers the DNA’s innate repair mechanisms to edit the gene. The team has used the technique to cure beta thalassemia in adult mice and in fetal mice in utero.

The PNA gene editing system doesn’t have the high-yield of CRISPER-Cas systems, but it does have the advantage of being less likely to make off-target modifications. According to Ly, that means their technique might be better for genetic diseases that only need to have a small percentage of cells corrected to make a therapeutic difference. For example, in the beta thalassemia studies, Ly and Glazer found that editing only six to seven percent of cells was curative.

Ly and Glazer plan to further refine and improve their technique through their participation in SCGE, and they look forward to sharing their results with the consortium and the greater biomedical community.

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Materials provided by Carnegie Mellon University. Original written by Jocelyn Duffy. Note: Content may be edited for style and length.

Zanzibar red colobus are found only in the Zanzibar archipelago and classified as Endangered by the IUCN Red List. Reliant on Unguja Island’s forests for their survival, around half of the species population is found in Jozani-Chwaka Bay National Park.

In the study, published in Oryx — The International Journal of Conservation, primatologists from Bangor University, in collaboration with national park managers from Zanzibar and the Wildlife Conservation Society (WCS), assessed mortality from vehicle collisions — a growing threat faced by primates living in increasingly fragmented habitats crisscrossed by roads.

They found that historic data from the road traversing the national park showed that one colobus was killed on average every 2-3 weeks by traffic. After speedbumps were installed, this was reduced to one every six weeks.

While great progress, this mortality rate is still a significant threat to the species — especially given that natural predation tends to target weaker individuals, yet roadkill is indiscriminate, killing reproductively active adults as well as the very young and old.

Bangor primatologist and Director of the Zanzibar Red Colobus Project, Dr. Alexander Georgiev, and senior author of this study, said: “Cars are not selective in the animals they kill. This means that while natural predators may target the very young and old more often, cars are equally likely to kill reproductively active young adults, who would contribute the most to population growth. And this may be a problem.”

Harry Olgun, now a PhD student at the University’s School of Natural Sciences, led this study as part of his Masters research on the road ecology of the Zanzibar red colobus. Olgun said: “After the road at Jozani was surfaced but before the speedbumps were installed, a colobus was reported to have been killed every two to three weeks, resulting in perhaps about 12-17 percent annual mortality, according to one estimate. The recent data show that speedbumps have made a huge difference for the safety of the colobus. Adding more speedbumps would help reduce the risk further.”

Dr. Tim Davenport, Director of Species Conservation & Science in Africa at WCS, who led the first countrywide census of the Zanzibar red colobus a few years ago and is a coauthor of the study, said: “As tourism grows in Zanzibar and habitat continues to shrink, using science to quantify and solve conservation problems has never been so important. Understanding the impact of vehicles on wildlife within a park, and implementing practical solutions is exactly what we as conservationists should be doing.”

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Materials provided by Wildlife Conservation Society. Note: Content may be edited for style and length.

Since spring 2020, researchers at Danderyd Hospital and Karolinska Institutet have conducted the so-called COMMUNITY study, with the main purpose of examining immunity after COVID-19. In the first phase of the study in spring 2020, blood samples were collected from 2,149 employees at Danderyd Hospital, of whom about 19 percent had antibodies against SARS-CoV-2. Blood samples have since then been collected every four months, and study participants have responded to questionnaires regarding long-term symptoms and their impact on the quality of life.

In the third follow-up in January 2021, the research team examined self-reported presence of long-term symptoms and their impact on work, social and home life for participants who had had mild COVID-19 at least eight months earlier. This group consisted of 323 healthcare workers (83 percent women, median age 43 years) and was compared with 1,072 healthcare workers (86 percent women, median age 47 years) who did not have COVID-19 throughout the study period.

The results show that 26 percent of those who had COVID-19 previously, compared to 9 percent in the control group, had at least one moderate to severe symptom that lasted more than two months and that 11 percent, compared to 2 percent in the control group, had a minimum of one symptom with negative impact on work, social or home life that lasted at least eight months. The most common long-term symptoms were loss of smell and taste, fatigue, and respiratory problems.

“We investigated the presence of long-term symptoms after mild COVID-19 in a relatively young and healthy group of working individuals, and we found that the predominant long-term symptoms are loss of smell and taste. Fatigue and respiratory problems are also more common among participants who have had COVID-19 but do not occur to the same extent,” says Charlotte Thålin, specialist physician, Ph.D. and lead researcher for the COMMUNITY study at Danderyd Hospital and Karolinska Institutet. “However, we do not see an increased prevalence of cognitive symptoms such as brain fatigue, memory and concentration problems or physical disorders such as muscle and joint pain, heart palpitations or long-term fever.”

“Despite the fact that the study participants had a mild COVID-19 infection, a relatively large proportion report long-term symptoms with an impact on quality of life. In light of this, we believe that young and healthy individuals, as well as other groups in society, should have great respect for the virus that seems to be able to significantly impair quality of life, even for a long time after the infection,” says Sebastian Havervall, deputy chief physician at Danderyd Hospital and PhD student in the project at Karolinska Institutet.

The COMMUNITY study will now continue, with the next follow-up taking place in May when a large proportion of study participants are expected to be vaccinated. In addition to monitoring immunity and the occurrence of re-infection, several projects regarding post- COVID are planned.

“We will, among other things, be studying COVID-19-associated loss of smell and taste more closely, and investigate whether the immune system, including autoimmunity, plays a role in post-COVID,” says Charlotte Thålin.

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Materials provided by Karolinska Institutet. Note: Content may be edited for style and length.