Your Beloved Pet Is Old. Should You Clone It?
Melvin was a special dog. A mixture of Catahoula and Doberman with black and tan markings, he was the office greeter, barking hellos to everyone who visited the Dupont Veterinary Clinic in Lafayette, Louisiana, which is owned by his human companions, Dr. Phillip Dupont and his wife, Paula. The couple say he's the best dog they ever owned.
When Melvin passed away, having two identical replicas helped ease the couple's grief.
He seemed to have an uncanny knack for understanding what they were saying, he could find lost car keys in tall grasses and the Duponts trusted him so much they felt comfortable having him babysit their grandson unattended in the backyard.
So when the 75-pound canine turned 9 and began to show signs of age, the Duponts sent off some of his skin cells to a lab in South Korea, the Sooam Biotech Research Foundation, to have him cloned. The Duponts toured the South Korean facilities and were satisfied that the animals were being treated well. While the first cloned puppy died from distemper, the second attempt produced two healthy animals—which the couple named Ken and Henry. When Melvin did pass away nearly two years later, in 2014, having two identical replicas helped ease the couple's grief. Even though it cost about $70,000 to clone Melvin, it was well worth it. "Melvin gave us a lot of pleasure," says Paula Dupont, "and this was less than the price of a new Land Cruiser."
As the technology improves, costs will tumble, making pet cloning more affordable for the mainstream.
The news has been filled recently with stories of celebrities such as Barbra Streisand or billionaire Barry Diller and his fashion icon wife, Diane von Furstenberg, spending big bucks to preserve their beloved pets—a practice New York magazine called "a laughable, extravagant waste of money." But cloning Fido isn't just for the ultra-wealthy anymore. Texas-based ViaGen now offers a domestic cloning service that will replicate Lassie for $50,000 and Garfield's kittens for a mere $25,000. While the exact number of cloned pets isn't known, the South Korean company says it has cloned about 800 pets while ViaGen has cloned about 100 cats and dogs. And as the technology improves, costs will tumble, making it more affordable for the mainstream, says Ron Gillespie, who heads PerPETuate, a Massachusetts-based outfit that collects and cryo preserves pet DNA, and works closely with ViaGen.
Even if the animals are genetic twins, biologists say, there are no guarantees their personalities will match, too.
While replicating Fido is becoming more feasible, should you? Animal rights organizations like The Humane Society and PETA are sharply critical of the practice, which is largely unregulated, and think it's outrageous to spend $50,000 or more to preserve Fluffy's genetic makeup when millions of cats and dogs are languishing in shelters and millions more are euthanized every year. And even if the animals are genetic twins, biologists say, there are no guarantees their personalities will match, too. Like humans, dogs' personalities are influenced by their environment and there are always variations in how the genes are expressed--although the Duponts say that Ken and Henry seem more like Melvin every day. "Their personalities are identical," says Paula.
Clones Ken and Henry, with Dr. Dupont and 10-year-old Melvin. Though all three dogs are genetic twins, their markings differ because the environment can influence how genes are expressed.
Still, the loss of a beloved pet can be incredibly painful, and in some cases, cloning can help deal with deep psychological wounds. When Monni Must's daughter died suddenly at age 28, the Michigan-based photographer adopted her child's black Lab, Billy Bean. As the dog got older and frailer, Must realized she couldn't handle losing her last link to her daughter—so she ponied up $50,000 to have the animal cloned. "I knew that I was falling apart," Must told Agence France-Presse. "The thought of Billy dying was just more than I could handle."
But these heated disputes miss what bioethicists believe is the real ethical dilemma—the fate of the female animals that provide the eggs and gestate the cloned puppies. "This issue tends to get framed as 'it's their personal choice, it's their money and they can do what they want with it,'" says Jessica Pierce, a bioethicist and author of Run, Spot, Run: The Ethics of Keeping Pets. "But this whole enterprise has all this collateral damage and behind-the-scenes impacts that people ignore. No one is talking about the dogs who are sacrificing themselves for this indulgence, and are suffering and being tormented just to have your clone."
"Even in the best-case scenarios, the cloned pet may go through several rounds of failed reproductive attempts—failed pregnancies, still births, and deformities."
Animal cloning, of course, is not new. Dolly, the sheep, made her debut in 1996 as the first cloned mammal. In 2005, Korea's Sooam Biotech cloned the first dog, and cloning horses and cows has become almost routine. Typically, the cloning process for dogs is fairly uncomplicated. It entails the use of a group of female dogs whose hormones are artificially manipulated with drugs to promote them to produce eggs. The eggs are then surgically harvested from donor dogs' ovaries. The immature eggs are stripped of their genetic information and then the pet's DNA is fused with the egg. When the embryo begins to develop, it is then transplanted to the womb of a surrogate dog.
However, cloning can have a high failure rate. When South Korea's Sooam Biotech lab cloned the first dog in 2005, there were 1000 failures—which means that number of eggs were fertilized and began to gestate, but at some point their development failed. And this figure doesn't include the number of dogs born with deformities serious enough that they are incompatible with life and need to be euthanized. "Even in the best-case scenarios, the cloned pet may go through several rounds of failed reproductive attempts—failed pregnancies, still births, and deformities," says Insoo Hyun, a bioethicist at Case Western Reserve University in Cleveland. "You can't do just one egg and one transfer. That won't happen. There is no guarantee that the very first time you will have a healthy animal. They're not miracle workers and you can't fight biology."
"You just have to let your pet go. It's all part of the experience."
But Ron Gillespie, who's been in the animal breeding business for decades, thinks these fears are overblown and that cloning is similar to the selective breeding that goes on all the time with cattle and even with champion racehorses. "We're really the victim of a lot of misinformation and misunderstanding," he says. "Right now, on average, we're dealing with three dogs: two that supply eggs and one to carry the embryo to term."
Still, this debate skirts the hard realities: dogs and cats simply have shorter lifespans than humans, and ethicists and animal rights activists believe there are better ways to deal with that grief. "You just have to let your pet go," says Hyun. "It's all part of the experience."
Catching colds may help protect kids from Covid
A common cold virus causes the immune system to produce T cells that also provide protection against SARS-CoV-2, according to new research. The study, published last month in PNAS, shows that this effect is most pronounced in young children. The finding may help explain why most young people who have been exposed to the cold-causing coronavirus have not developed serious cases of COVID-19.
One curiosity stood out in the early days of the COVID-19 pandemic – why were so few kids getting sick. Generally young children and the elderly are the most vulnerable to disease outbreaks, particularly viral infections, either because their immune systems are not fully developed or they are starting to fail.
But solid information on the new infection was so scarce that many public health officials acted on the precautionary principle, assumed a worst-case scenario, and applied the broadest, most restrictive policies to all people to try to contain the coronavirus SARS-CoV-2.
One early thought was that lockdowns worked and kids (ages 6 months to 17 years) simply were not being exposed to the virus. So it was a shock when data started to come in showing that well over half of them carried antibodies to the virus, indicating exposure without getting sick. That trend grew over time and the latest tracking data from the CDC shows that 96.3 percent of kids in the U.S. now carry those antibodies.
Antibodies are relatively quick and easy to measure, but some scientists are exploring whether the reactions of T cells could serve as a more useful measure of immune protection.
But that couldn't be the whole story because antibody protection fades, sometimes as early as a month after exposure and usually within a year. Additionally, SARS-CoV-2 has been spewing out waves of different variants that were more resistant to antibodies generated by their predecessors. The resistance was so significant that over time the FDA withdrew its emergency use authorization for a handful of monoclonal antibodies with earlier approval to treat the infection because they no longer worked.
Antibodies got most of the attention early on because they are part of the first line response of the immune system. Antibodies can bind to viruses and neutralize them, preventing infection. They are relatively quick and easy to measure and even manufacture, but as SARS-CoV-2 showed us, often viruses can quickly evolve to become more resistant to them. Some scientists are exploring whether the reactions of T cells could serve as a more useful measure of immune protection.
Kids, colds and T cells
T cells are part of the immune system that deals with cells once they have become infected. But working with T cells is much more difficult, takes longer, and is more expensive than working with antibodies. So studies often lags behind on this part of the immune system.
A group of researchers led by Annika Karlsson at the Karolinska Institute in Sweden focuses on T cells targeting virus-infected cells and, unsurprisingly, saw that they can play a role in SARS-CoV-2 infection. Other labs have shown that vaccination and natural exposure to the virus generates different patterns of T cell responses.
The Swedes also looked at another member of the coronavirus family, OC43, which circulates widely and is one of several causes of the common cold. The molecular structure of OC43 is similar to its more deadly cousin SARS-CoV-2. Sometimes a T cell response to one virus can produce a cross-reactive response to a similar protein structure in another virus, meaning that T cells will identify and respond to the two viruses in much the same way. Karlsson looked to see if T cells for OC43 from a wide age range of patients were cross-reactive to SARS-CoV-2.
And that is what they found, as reported in the PNAS study last month; there was cross-reactive activity, but it depended on a person’s age. A subset of a certain type of T cells, called mCD4+,, that recognized various protein parts of the cold-causing virus, OC43, expressed on the surface of an infected cell – also recognized those same protein parts from SARS-CoV-2. The T cell response was lower than that generated by natural exposure to SARS-CoV-2, but it was functional and thus could help limit the severity of COVID-19.
“One of the most politicized aspects of our pandemic response was not accepting that children are so much less at risk for severe disease with COVID-19,” because usually young children are among the most vulnerable to pathogens, says Monica Gandhi, professor of medicine at the University of California San Francisco.
“The cross-reactivity peaked at age six when more than half the people tested have a cross-reactive immune response,” says Karlsson, though their sample is too small to say if this finding applies more broadly across the population. The vast majority of children as young as two years had OC43-specific mCD4+ T cell responses. In adulthood, the functionality of both the OC43-specific and the cross-reactive T cells wane significantly, especially with advanced age.
“Considering that the mortality rate in children is the lowest from ages five to nine, and higher in younger children, our results imply that cross-reactive mCD4+ T cells may have a role in the control of SARS-CoV-2 infection in children,” the authors wrote in their paper.
“One of the most politicized aspects of our pandemic response was not accepting that children are so much less at risk for severe disease with COVID-19,” because usually young children are among the most vulnerable to pathogens, says Monica Gandhi, professor of medicine at the University of California San Francisco and author of the book, Endemic: A Post-Pandemic Playbook, to be released by the Mayo Clinic Press this summer. The immune response of kids to SARS-CoV-2 stood our expectations on their head. “We just haven't seen this before, so knowing the mechanism of protection is really important.”
Why the T cell immune response can fade with age is largely unknown. With some viruses such as measles, a single vaccination or infection generates life-long protection. But respiratory tract infections, like SARS-CoV-2, cause a localized infection - specific to certain organs - and that response tends to be shorter lived than systemic infections that affect the entire body. Karlsson suspects the elderly might be exposed to these localized types of viruses less often. Also, frequent continued exposure to a virus that results in reactivation of the memory T cell pool might eventually result in “a kind of immunosenescence or immune exhaustion that is associated with aging,” Karlsson says. https://leaps.org/scientists-just-started-testing-a-new-class-of-drugs-to-slow-and-even-reverse-aging/particle-3 This fading protection is why older people need to be repeatedly vaccinated against SARS-CoV-2.
Policy implications
Following the numbers on COVID-19 infections and severity over the last three years have shown us that healthy young people without risk factors are not likely to develop serious disease. This latest study points to a mechanism that helps explain why. But the inertia of existing policies remains. How should we adjust policy recommendations based on what we know today?
The World Health Organization (WHO) updated their COVID-19 vaccination guidance on March 28. It calls for a focus on vaccinating and boosting those at risk for developing serious disease. The guidance basically shrugged its shoulders when it came to healthy children and young adults receiving vaccinations and boosters against COVID-19. It said the priority should be to administer the “traditional essential vaccines for children,” such as those that protect against measles, rubella, and mumps.
“As an immunologist and a mother, I think that catching a cold or two when you are a kid and otherwise healthy is not that bad for you. Children have a much lower risk of becoming severely ill with SARS-CoV-2,” says Karlsson. She has followed public health guidance in Sweden, which means that her young children have not been vaccinated, but being older, she has received the vaccine and boosters. Gandhi and her children have been vaccinated, but they do not plan on additional boosters.
The WHO got it right in “concentrating on what matters,” which is getting traditional childhood immunizations back on track after their dramatic decline over the last three years, says Gandhi. Nor is there a need for masking in schools, according to a study from the Catalonia region of Spain. It found “no difference in masking and spread in schools,” particularly since tracking data indicate that nearly all young people have been exposed to SARS-CoV-2.
Both researchers lament that public discussion has overemphasized the quickly fading antibody part of the immune response to SARS-CoV-2 compared with the more durable T cell component. They say developing an efficient measure of T cell response for doctors to use in the clinic would help to monitor immunity in people at risk for severe cases of COVID-19 compared with the current method of toting up potential risk factors.
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on new scientific theories and progress to give you a therapeutic dose of inspiration headed into the weekend.
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Here are the stories covered this week:
- The eyes are the windows to the soul - and biological aging?
- What bean genes mean for health and the planet
- This breathing practice could lower levels of tau proteins
- AI beats humans at assessing heart health
- Should you get a nature prescription?