Tag: dna

“Mini Antlers” Grown On Mice Heads After Scientists Implant Deer Cells

Scientists have grown “mini-antlers” on mice by inserting deer genes into the mouse genome, according to a new paper. The results suggest that mammals that have lost the ability to regenerate organs may still contain some regenerative genes, and that it may be possible to harness the rapid growth of antlers in other applications. 

Growing at 2.75 centimeters (around 1 inch) per day, antlers are one of the fastest regenerating tissues in the animal kingdom and offer a perfect look at how mammals can regenerate cells on a regular basis. Antlers are especially interesting because mammals in general have lost the ability to regenerate organs and most other tissues, so a large appendage that regularly regrows offers unparalleled insight into how regenerative medicine for bones could work.  

In the pursuit of regenerative medicines, Chinese researcher Toa Qin and colleagues took a deep dive into the mechanics behind the antlers of Sika deer, which regrow every year before they are shed. In doing so, they created a regenerative “atlas” of Sika deer antlers, isolating multiple single cells and genes that are critical in the development of the antler tissue. 

Ten days before the antlers were shed, the researchers identified one type of stem cell that was highly active in the regeneration, and these remained with the antlers a short time after shedding. However, by day five post-shedding, a new subtype of stem cells had emerged. 

After identifying multiple stages of growth, the team took the stem cells with the most regrowth potential (which proved to be from shed antlers around five days old) and cultured them in a Petri dish before implanting them into the head of mice. 

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Scientists create mice with two fathers after making eggs from male cells

Scientists have created mice with two biological fathers by generating eggs from male cells, a development that opens up radical new possibilities for reproduction.

The advance could ultimately pave the way for treatments for severe forms of infertility, as well as raising the tantalising prospect of same-sex couples being able to have a biological child together in the future.

“This is the first case of making robust mammal oocytes from male cells,” said Katsuhiko Hayashi, who led the work at Kyushu University in Japan and is internationally renowned as a pioneer in the field of lab-grown eggs and sperm.

Hayashi, who presented the development at the Third International Summit on Human Genome Editing at the Francis Crick Institute in London on Wednesday, predicts that it will be technically possible to create a viable human egg from a male skin cell within a decade. Others suggested this timeline was optimistic given that scientists are yet to create viable lab-grown human eggs from female cells.

Previously scientists have created mice that technically had two biological fathers through a chain of elaborate steps, including genetic engineering. However, this is the first time viable eggs have been cultivated from male cells and marks a significant advance. Hayashi’s team is now attempting to replicate this achievement with human cells, although there would be significant hurdles for the use of lab-grown eggs for clinical purposes, including establishing their safety.

“Purely in terms of technology, it will be possible [in humans] even in 10 years,” he said, adding that he personally would be in favour of the technology being used clinically to allow two men to have a baby if it were shown to be safe.

“I don’t know whether they’ll be available for reproduction,” he said. “That is not a question just for the scientific programme, but also for [society].”

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Scientists to engineer woolly mammoth’s return by 2027

The long-extinct woolly mammoth is slated for a return to the world stage by 2027, Popular Mechanics reported Monday of biotechnology startup Colossal’s ambitious project.

“It will walk like a woolly mammoth, look like one, sound like one, but most importantly, it will be able to inhabit the same ecosystem previously abandoned by the mammoth’s extinction,” the Texas-based, billion-dollar company said of its landmark de-extinction project.

“The woolly mammoth is a vital defender of the earth,” the site also says.

Colossal Laboratories & Biosciences began making headlines again after recent press releases highlighting their work on similar projects to “de-extinct” other ancient creatures like the dodo bird.

“In addition to bringing back ancient extinct species like the woolly mammoth, we will be able to leverage our technologies to help preserve critically endangered species that are on the verge of extinction and restore animals where humankind had a hand in their demise,” said CEO and Colossal co-founder Ben Lamm on the organization’s website.

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Scientist who edited babies’ genes says he acted ‘too quickly’

The scientist at the heart of the scandal involving the world’s first gene-edited babies has said he moved “too quickly” by pressing ahead with the procedure.

He Jiankui sent shock waves across the world of science when he announced in 2018 that he had edited the genes of twin girls, Lulu and Nana, before birth. He was subsequently sacked by his university in Shenzhen, received a three-year prison sentence, and was broadly condemned for having gone ahead with the risky, ethically contentious and medically unjustified procedure with inadequate consent from the families involved.

Speaking to the Guardian in one of his first interviews since his public re-emergence last year, He said: “I’ve been thinking about what I’ve done in the past for a long time. To summarise it up in one sentence: I did it too quickly.”

However, he stopped short of expressing regret or apologising, saying “I need more time to think about that” and “that’s a complicated question”.

He declined to elaborate on what he believed ought to have been in place before proceeding with gene editing, but said he would give further details at an invited talk he is scheduled to give at the University of Oxford next month.

He studied physics in China before moving to the US to study for a PhD at Rice University and a post-doctorate in genome sequencing at Stanford University. He returned to China in 2012 to pursue Crispr-Cas9 gene-editing research, launching a variety of biotechnology business ventures.

Gene-edited cells were already beginning to be used in clinical treatments for adults. But genetically modifying embryos was – and is – far more ethically contentious, because changes are made to every cell in the body and are passed down to subsequent generations. Some question whether such a step could ever be medically justified.

Against this backdrop, He dropped the bombshell at an international conference in Hong Kong four years ago that he had modified two embryos before they were placed in their mother’s womb. It later emerged that a third gene-edited baby had been born.

The edit, of a gene called CCR5, targeted a pathway used by the HIV virus to enter cells, and was claimed to give the babies immunity to HIV.

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Geneticists Intend To Bring The Dodo Bird Back From Extinction

Scientists believe they have found a way to bring back the animal most synonymous with the extinction, the dodo bird. Should their endeavor prove successful, this could open the door for the resurrection of several other animals that were thought to be long gone.

A “de-extinction company” known as Colossal Biosciences has decided to play God and right a “wrong” done by humans by using edited DNA to create a so-called proxy version of the dodo since an exact clone is not possible. Should the recreation prove successful, the next step would be to re-introduce the dodo to its original habitat in Mauritius.

The founders of the company believes reintroducing the dodo will benefit conservation and the wildlife ecosystem. They do not elaborate on why, however.

Colossal Biosciences is also working bringing other endangered species back from the dead, such as the Tasmanian tiger and wooly mammoth.

Here is the story from Vice fully explaining the process for “de-extincting” the dodo and the many challenges Colossal Biosciences faces:

Colossal Biosciences, founded in 2021 by entrepreneur Ben Lamb and Harvard geneticist George Church, announced on Tuesday that it plans to resurrect and rewild the dodo, the iconic flightless bird that has become a powerful symbol of extinction after it was rapidly wiped out as a result of human interference on its native island of Mauritius.

Colossal is already working on efforts to de-extinct the wooly mammoth and thylacine (aka the Tasmanian tiger), and reintroduce them to wild habitats. In the process, the company hopes to pioneer new technologies with applications in conservation biology and human healthcare, to name a few.

Now, the company has added the dodo to its de-extinction wishlist and tapped Beth Shapiro, an evolutionary biologist at the University of Santa Cruz, to back the project. The team envisions the return of a “proxy” version of this idiosyncratic bird, meaning a species with edited DNA as opposed to an exact clone, to its original habitat in Mauritius.

“I think this is an opportunity where, given the man-made nature of the extinction of the dodo, man could not only bring the dodo back, but also fix what was done to parts of the ecosystem to reintroduce them,” noted Lamm in the same call. “There’s a lot of benefits from a conservation perspective, in terms of what we can learn from rewilding.”

The flightless bird was such a one-off that its closest living relative is the Nicobar pigeon, a colorful flying bird that looks completely different from its famous extinct cousin. The bizarre appearance distinguished the dodo as a cultural curiosity practically from the moment European explorers came across it during the 17th century.

Now, Shapiro and her colleagues are tackling the challenge of stitching together a dodo-like animal using genomes that have been sequenced from real dodo specimens, as well as genomes from their close relatives, such as the Nicobar pigeon and the Rodrigues solitaire, another extinct flightless bird that lived on the nearly island of Rodrigues. Indeed, de-extincting the dodo will have to start with reverse-engineering it.

“Once a species is extinct, it’s really not possible to bring back an identical copy,” Shapiro said. “The hope is that we can use, first, comparative genomics so we can get at least one, and hopefully more, dodo genomes that we can use to look and see how dodos are similar to each other, and different from things like the solitaire.”

From there, the team will “compare those to the Nicobar pigeon, and other pigeons, and identify mutations in that genome that we believe may have some phenotypic impact that made the dodo look like a dodo instead of like a Nicobar pigeon,” she continued.

Getting the right genetic ingredients for a dodo proxy is only the first hurdle in what may be a long scientific quest. The researchers will also have to figure out how to get a dodo embryo into an egg so that a new generation of birds can successfully hatch.

As with many emerging fields, the science of de-extinction contains many ethical nuances in addition to its technical challenges. Tom Gilbert, who serves as director of the University of Copenhagen’s Center for Evolutionary Hologenomics, told Motherboard that proxies for extinct species may well be technically feasible, but that is only the beginning of the conversation.

“The question really is, how close will the proxy be to the extinct form?” said Gilbert, who recently joined Colossal’s advisory board, in an email. “That’s a much harder question, and not straightforward to answer, given it raises the question…what are you measuring? Genomic similarity? Physical similarity? Similarity in the niche it fills/what it does, even if it doesn’t look the same (e.g. if you can make an elephant able to live in the cold where it acts like a mammoth…is that enough??

“For reasons I’ve argued before in various articles I think that the best we can hope for is something that is an equivalent with regard to the niche it fills,” he continued. “This raises the question of is it worth it? Here it’s also not black and white. Sometimes maybe, but in other cases maybe the environment is so changed already that the hope of free living populations is far from what can be done. One has to bear in mind e.g. how much, relatively, human untouched environment is left.”

There are other dilemmas to consider if the dodo were to be resurrected. The first dilemma is how to protect the bird from another extinction.

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Scientists Use CRISPR To Put Genes From Alligator Into Catfish

Millions of fish are farmed in the US every year, but many of them die from infections. In theory, genetically engineering fish with genes that protect them from disease could reduce waste and help limit the environmental impact of fish farming. A team of scientists have attempted to do just that—by inserting an alligator gene into the genomes of catfish.

Americans go through a lot of catfish. In 2021, catfish farms in the US produced 307 million pounds (139 million kilogram) of the fish. “On a per-pound basis, anywhere from 60 to 70% of US aquaculture is … catfish production,” says Rex Dunham, who works on the genetic improvement of catfish at Auburn University in Alabama.

But catfish farming is also a great breeding ground for infections. From the time farmed fish are newly hatched to the time they are harvested, around 40% of the animals worldwide die from various diseases, says Dunham.

Could the new genetic modification help?

The alligator gene, which Dunham’s research turned up as a potential answer, codes for a protein called cathelicidin. The protein is antimicrobial, says Dunham—it’s thought to help protect alligators from developing infections in the wounds they sustain during their aggressive fights with each other. Dunham wondered whether animals that have the gene artificially inserted into their genomes might be more resistant to diseases.

Dunham and his colleagues also wanted to go a step further and ensure that the resulting transgenic fish couldn’t reproduce. That’s because genetically modified animals have the potential to wreak havoc in the wild should they escape from farms, outcompeting their wild counterparts for food and habitat.

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Scientists Have Successfully Reversed Signs of Aging in Mice for the First Time

Two research groups in the US were able to stop mice from getting old by fixing their DNA.

In a recent study published in Cell on Jan. 12, Harvard scientists showed that they could manipulate and reverse the aging process in mice by generating DNA repairs.

The results of a 13-year, international study show for the first time that breakdown in epigenetic information accelerates aging in mice and that repairing the epigenome can reverse those signs of aging.

“For about the past 50 years, popular theory has held that the process of aging is caused in large part by an accumulation of mutation. There’s growing evidence, however, that aging has a significant epigenetic component. That is, the process by which stretches of DNA or the genes are turned on and off,” said the paper’s senior author, David Sinclair, professor of genetics at the Blavatnik Institute at Harvard Medical School and co-director of the Paul F. Glenn Center for Biology of Aging Research.

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DNA Used to Uncover 70s Serial Killer Who Raped and Strangled College Student in Ohio

Hamilton County Prosecutor Joseph T. Deters announced the indictment of Ralph Howell for the rape and murder of Cheryl Thompson in 1978.

Howell was killed in an automobile accident in 1985.

Howell was posthumously indicted for one count of Aggravated Murder, and one count of Rape.

On March 24, 1978, Cheryl Thompson went missing after leaving her home to meet her boyfriend at a bar in Oakley.

On April 8, 1978, Thompson’s body was discovered along the bank of the Little Miami River by an Ohio Department of Natural Resources officer. Thompson’s cause of death was asphyxia caused by strangulation. It was also determined Thompson had been raped.

Physical evidence was collected from Thompson’s body and stored at the Hamilton County Coroner’s Office. However, due to the forensic limitations of the time, the investigation quickly went cold. Loveland police officers and agents at the Bureau of Criminal Investigations never stopped investigating.

This year, the DNA sample taken from Thompson’s body was sent to a third-party genealogy company in hopes of developing a suspect. The results narrowed this DNA sample to a specific family tree. Ralph Howell was included in these results.

Further investigation showed Howell was arrested in 1983 for abduction. In that incident, Howell picked a woman up on the side of the road and offered to drive her home. Once in the vehicle, Howell placed a rope around the victim’s neck and began to strangle her. He told her he wanted to have sex with her. The victim was able to fight Howell off and escape from the vehicle.

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China’s Collection of DNA Data Linked to Bioweapons, Religious Persecution, Organ Harvesting

Police in China’s Fuzhou City recently bragged about solving a break-in by conducting a DNA test of a blood smear from a mosquito that allegedly stung the burglar. However, the incident, which made global headlines, brings to the fore the threats associated with the exploitation of DNA databases.

The Chinese Communist Party’s (CCP) ambitious efforts to collect genomic data—from inside and outside of China—to solve crimes and maintain social control have already been raising concerns for years.

The National Counterintelligence and Security Center has warned that the CCP, for years, has been collecting American healthcare and DNA data, through both legal and illegal means. U.S. officials recently said that such sensitive data might be potentially exploited by American enemies to create targeted biological weapons.

“There are now weapons under development, and developed, that are designed to target specific people,” Rep. Jason Crow (D-Colo.) reportedly said at the Aspen Security Forum in July this year.

“That’s what this is, where you can actually take someone’s DNA … their medical profile, and you can target a biological weapon that will kill that person or take them off the battlefield or make them inoperable.”

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Ancient DNA analysis sheds light on the early peopling of South America

The Americas were the last continent to be inhabited by humans. An increasing body of archaeological and genomic evidence has hinted to a complex settlement process. This is especially true for South America, where unexpected ancestral signals have raised perplexing scenarios for the early migrations into different regions of the continent.

Many unanswered questions still persist, such as whether the first humans migrated south along the Pacific coast or by some other route. While there is archaeological evidence for a north-to-south migration during the initial peopling of the Americas by ancient Indigenous peoples, where these ancient humans went after they arrived has remained elusive.

Using DNA from two ancient human individuals unearthed in two different archaeological sites in northeast Brazil—Pedra do Tubarão and Alcobaça—and powerful algorithms and genomic analyses, Florida Atlantic University researchers in collaboration with Emory University have unraveled the deep demographic history of South America at the regional level with some unexpected and surprising results.

Not only do researchers provide new genetic evidence supporting existing archaeological data of the north-to-south migration toward South America, they also have discovered migrations in the opposite direction along the Atlantic coast—for the first time. The work provides the most complete genetic evidence to date for complex ancient Central and South American migration routes.

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