This article was originally published on The Conversation, an independent and nonprofit source of news, analysis and commentary from academic experts. Disclosure information is available on the original site.

Author: Francoise Baylis, Professor and Canada Research Chair in Bioethics and Philosophy, Dalhousie University

Shoukhrat Mitalipov, a reproductive biologist at Oregon Health and Science University, is nothing if not a pioneer. In 2007, his team published proof-of-principle research in primates showing it was possible to derive stem cells from cloned primate embryos. In 2013, his team was the first to create human embryonic stem cells by cloning. Now, in 2017, his team is reported to have safely and effectively modified human embryos using the gene editing technique CRISPR.

Mitalipovs team is not the first to genetically modify human embryos. This was first accomplished in 2015 by a group of Chinese scientists led by Junjiu Huang. Mitalipovs team, however, may be the first to demonstrate basic safety and efficacy using the CRISPR technique.

This has serious implications for the ethics debate on human germline modification which involves inserting, deleting or replacing the DNA of human sperm, eggs or embryos to change the genes of future children.

Ethically controversial

Those who support human embryo research will argue that Mitalipovs research to alter human embryos is ethically acceptable because the embryos were not allowed to develop beyond 14 days (the widely accepted international limit on human embryo research) and because the modified embryos were not used to initiate a pregnancy. They will also point to the future potential benefit of correcting defective genes that cause inherited disease.

This research is ethically controversial, however, because it is a clear step on the path to making heritable modifications genetic changes that can be passed down through subsequent generations.

Beyond safety and efficacy

Internationally, UNESCO has called for a ban on human germline gene editing. And the Convention for the Protection of Human Rights and Dignity of the Human Being with regard to the Application of Biology and Medicine the Oviedo Convention specifies that an intervention seeking to modify the human genome may only be undertaken for preventive, diagnostic or therapeutic purposes and only if its aim is not to introduce any modification in the genome of any descendants.

In a move away from the positions taken by UNESCO and included in the Oviedo Convention, in 2015 the 12-person Organizing Committee of the first International Summit on Human Gene Editing (of which I was a member) issued a statement endorsing basic and preclinical gene editing research involving human embryos.

The statement further stipulated, however, that: It would be irresponsible to proceed with any clinical use of germline editing unless and until (i) the relevant safety and efficacy issues have been resolved, based on appropriate understanding and balancing of risks, potential benefits, and alternatives, and (ii) there is broad societal consensus about the appropriateness of the proposed application.

Mitalipovs research aims to address the first condition about safety and efficacy. But what of the second condition which effectively recognizes that the human genome belongs to all of us and that it is not for scientists or other elites to decree what should or should not happen to it?

Modification endorsed

Since the 2015 statement was issued, many individuals and groups have tried to set aside the recommendation calling for a broad societal consensus.

For example, in February 2017, the U.S. National Academy of Sciences and National Academy of Medicine published a report endorsing germline modification. It states unequivocally that clinical trials using heritable germline genome editing should be permitted provided the research is only for compelling reasons and under strict oversight limiting uses of the technology to specified criteria.

Seeds of change in Canada

In Canada, it is illegal to modify human germ cells. Altering the genome of a cell of a human being or in vitro embryo such that the alteration is capable of being transmitted to descendants is among the activities prohibited in the 2004 Assisted Human Reproduction Act.

Worried that Canadian researchers may fall behind on the international scene and that restrictive research policies may lead to medical tourism, the Canadian Institutes for Health Research (with input from the Canadian Stem Cell Network) has begun to plant the seeds of change.

In its Human Germline Gene Editing report, CIHR hints at the benefits of changing the legislation. It also suggests professional self-regulation and research funding guidelines could replace the current federal statutory prohibition.

Future of the species

With the recent announcement of Mitalipovs technological advances and increasing suggestions from researchers that heritable modifications to human embryos be permitted, it is essential that citizens be given opportunities to think through the ethical issues and to work towards broad societal consensus.

We are talking about nothing less than the future of the human species. No decisions about the modification of the germline should be made without broad societal consultation.

Nothing about us without us!

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Human genome editing: We should all have a say - National Post

U.S. scientists have succeeded in alteringthe genes of a human embryo to correct a disease-causingmutation, making it possible to prevent the defect from beingpassed on to future generations.The milestone, published this week in the journal Nature,was confirmed last week by Oregon Health and Science University(OHSU), which collaborated with the Salk Institute and Korea'sInstitute for Basic Science to use a technique known asCRISPR-Cas9 to correct a genetic mutation for a heart condition.Until now, published studies using the technique had beendone in China with mixed results.

CRISPR-Cas9 works as a type of molecular scissors that canselectively trim away unwanted parts of the genome, and replaceit with new stretches of DNA."We have demonstrated the possibility to correct mutationsin a human embryo in a safe way and with a certain degree ofefficiency," said Juan Carlos Izpisua Belmonte, a professor inSalk's Gene Expression Laboratory and a co-author of the study.To increase the success rate, his team introduced the genomeediting components along with sperm from a male with thetargeted gene defect during the in vitro fertilization process.

They found that the embryo used the available healthy copy ofthe gene to repair the mutated part.The Salk/OHSU team also found that its gene correction didnot cause any detectable mutations in other parts of the genome a major concern for gene editing.Still, the technology was not 100 per cent successful it increased the number of repaired embryos from 50 per cent, whichwould have occurred naturally, to 74 per cent.The embryos, tested in the laboratory, were allowed todevelop for only a few days."There is still much to be done to establish the safety ofthe methods, therefore they should not be adopted clinically,"Robin Lovell-Badge, a professor at London's Francis CrickInstitute who was not involved in the study, said in astatement.

Washington's National Academy of Sciences (NAS) earlier thisyear softened its previous opposition to the use of gene editingtechnology in human embryos, which has raised concerns it couldbe used to create so-called designer babies. There is also afear of introducing unintended mutations into the "germline,"meaning cells that become eggs or sperm."No one is thinking about this because it is practicallyimpossible at this point," Izpisua Belmonte said. "This is stillvery basic research let alone something as complex as whatnature has done for millions and millions of years ofevolution."An international group of 11 organizations, including theAmerican Society of Human Genetics and Britain's Wellcome Trust,on Wednesday issued a policy statement recommending againstgenome editing that culminates in human implantation andpregnancy, while supporting publicly funded research into itspotential clinical applications.The latest research involved a gene mutation linked tohypertrophic cardiomyopathy, the most common cause of suddendeath in otherwise healthy young athletes. It affects around 1in 500 people.Salk's Izpisua Belmonte, emphasizing that much more study isneeded, said the most important practical application for thenew technology could be in correcting genetic mutations inbabies either while they are still in utero or right after theyare born."It is crucial that we continue to proceed with the utmostcaution, paying the highest attention to ethicalconsiderations," he said.

Canada's Assisted Human Reproduction Actbans any manipulation of the human genome that can be transmitted to the next generation.

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Scientists alter genes of human embryo to correct disease-causing mutation - CBC.ca

Whats the weight?

Jenny Elia Pfeiffer/Getty

By Jessica Hamzelou

SINCE the first test tube baby arrived 39 years ago, an estimated 6.5 million children have been born thanks to IVF and similar techniques. But we are only just starting to learn about the long-term health of people conceived using assisted reproduction techniques (ART), who may have a higher risk of obesity in later life.

Today, 1 in every 30 babies in Japan is conceived by ART, says Tomoya Hasegawa of Tokyo Medical University. These babies are usually healthy, but tend to have a lower birth weight. Large studies that didnt look at conception method have previously found that low birth weight is linked to adult obesity and diabetes.

To investigate further, Heleen Zandstra of Maastricht Medical Centre, the Netherlands, and her team have been comparing the effects of using two different culture media to support the growth of early IVF embryos. Earlier they had found that one of these was associated with babies that were 112 grams lighter at birth than those beginning life in the other medium. Thats a big difference, considering babies only weigh about 3 kilograms, says Zandstra.

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Now the team have followed up on these babies at the age of 9, recording the height, weight and fat mass of 136 children, as well as blood pressure and heart rate.

They were surprised to find that, while children conceived using each type of culture medium were around the same height, the BMI of the group that had been lighter at birth was an average of 0.9 lower than those who had been heavier babies. There was a difference in weight of 2 kilograms, says Zandstra.

Given that heavier children are more likely to develop obesity later on, the results are worrying

However, both groups were heavier than average 9-year-olds living in similar circumstances, and had more abdominal fat. Given that heavier children are more likely to become obese later in life, the results are worrying, says Zandstra, who presented her findings at the annual meeting of the European Society of Human Reproduction and Embryology (ESHRE) in Switzerland in July.

At the same meeting, Hasegawa presented his analysis of 1830 children in Japan. His team found that babies conceived using ART were heavier than naturally conceived babies when they were born, but there was no real difference at 18 months. However, the ART children were heavier again at 6 years old. The results were surprising, says Hasegawa.

What this might mean for adult health in unknown. Louise Brown, the first person born via IVF, is only 39 we dont know yet what will happen to IVF-conceived people in their 50s, says Zandstra.

But people neednt be wary of fertility treatment. We know that IVF is safe, because we have so many children, says Arianna DAngelo, who coordinates the ESHRE group on safety in assisted reproduction. We shouldnt worry, but we should be doing more to monitor children. Studies might flag up problems later in life, says DAngelo.

This article appeared in print under the headline IVF babies grow up to be heavier

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IVF babies grow up heavier and may have higher risk of obesity - New Scientist

Dr. Ryan Riggs sees them almost every day in his fertility clinic at Research Medical Center: Kansas City men struggling with low sperm counts.

Now he knows theyre part of a much larger trend that threatens the population stability of several developed nations, including the United States.

A large-scale study published last week in the journal Human Reproduction Update found that sperm counts declined 59 percent in men from the U.S., Europe, Australia and New Zealand over a 38-year period that ended in 2011. Men in less developed nations in Asia, South America and Africa exhibited no such decline.

This is amazing, Riggs said. I dont want to be an alarmist but what if, in another 40 years, the numbers are 50 percent lower?

The birth rate in the U.S. is already at a historic low, and Riggs noted that were it not for immigration, the country would be like some in Western Europe with declining populations and shrinking workforces struggling to support the needs of the elderly.

Riggs called the dropping sperm counts a societal, macro-epidemiological problem.

It has very significant and grave implications, Riggs said. It means Ill have patients in the short term, but in the long term its concerning.

Riggs opened Blue Sky Fertility last October after previously working at a large clinic called Conceptions Reproductive Associates in Colorado.

He said what he has seen personally fits with the results of the much larger study.

We certainly feel like we see an increasing frequency of gentlemen who have abnormal sperm counts, Riggs said. In fact, if you look at the data, in 40 or perhaps even 50 percent of couples, sperm is a factor in their struggle to conceive.

The studys authors expressed similar shock and concern at the results, but did not offer any possible explanations for the stark difference between men in the two cohorts.

Riggs pointed to two potential factors driving down sperm counts in developed nations: unhealthy diets and near-constant exposure to chemicals that alter hormone production.

I personally would look to the endocrine disruptors and obesity as significant factors impacting sperm health, Riggs said.

While its hard to avoid endocrine disruptors such as phthalates, which are in deodorants and perfumes and leach from all kinds of plastic products, Riggs said maintaining a healthy weight which has long been known to help with fertility is an important step to take before fertility treatments.

There are folks who come through my door and I have to advise them, Before we go down this route and potentially spend a lot of money, we need to optimize your health, Riggs said.

On a larger level, Riggs said he would be interested in more research to see if there are sperm count differences within different regions in the U.S. and to find out if immigrants sperm counts decline after they move to U.S. and how quickly.

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Study shows Western men's sperm counts are in freefall and KC is no exception - Kansas City Star

An international team of scientists analyzed data from men around the world and found sperm counts declining in Western countries. Hanna Barczyk for NPR hide caption

An international team of scientists analyzed data from men around the world and found sperm counts declining in Western countries.

Sperm counts appear to be plummeting throughout the Western world, according to a large study of men around the world.

An international team of scientists analyzed data from nearly 43,000 men in dozens of industrialized countries and found that sperm counts dropped by more than half over nearly four decades.

"I think that we should take this very seriously," says Shanna Swan, a reproductive epidemiologist at the Icahn School of Medicine at Mount Sinai in New York. She helped conduct the study published in the journal Human Reproduction Update. "I think it's a wake-up call," Swan says.

Previous studies have suggested that sperm counts may be falling around the world. This study is the largest and most comprehensive to date. It was designed to resolve doubts about the earlier findings, Swan says.

"I've always been very skeptical of previous reports that have suggested that sperm counts are declining," says Allan Pacey, a professor of andrology at the University of Sheffield in England who was not involved in the new research. "I'm a bit more of a believer that sperm counts are declining than I was at this time yesterday," he says.

Even at the reduced sperm counts, infertility has not become a widespread problem. At the most, the lower levels of sperm may make it harder for some couples to conceive, Pacey says.

But there's no sign the decline is slowing, which means that male infertility could become a more common problem in the future.

"Since this is the best study that's ever been done, it is concerning that it suggests such a progressive and dramatic decrease in sperm counts over time," says Peter Schlegel, a professor and chairman of urology at Weill Cornell Medicine in New York. Schlegel serves as vice president of the American Society for Reproductive Medicine.

Schlegel stresses, however, that more research is needed to confirm the findings and try to determine possible causes.

"Since we don't know what could be causing it, it's worrisome," Schlegel says.

Swan and her colleagues combed the scientific literature for studies that had examined sperm counts and concentrations and screened more than 7,000 studies, excluding those that had shortcomings or flaws. The researchers then analyzed data collected by 185 studies of 42,935 men who provided semen samples between 1973 and 2011 in North America, Europe, Australia and New Zealand.

One of the ways the researchers tried to alleviate concerns about previous studies was to include men who weren't just being tested at fertility clinics because they might be infertile. They included sperm counts from other men soldiers and college students, for example.

The analysis found an overall 52.4 percent decline in sperm concentration and a 59.3 percent decline in the total sperm count over the 39-year period. (Sperm concentration is the measure of the concentration of sperm in a man's sample how many millions of sperm are in a milliliter of semen. Total sperm count is the number doctors get when they multiply that by the volume of the sample.)

"I think these are extremely concerning findings," Swan says.

And Swan says it's not just the concern about fertility. A decreased sperm count has been linked to an increased risk for premature death, Swan says. So it may be a marker for other health problems, she says.

While no one knows why sperm counts and concentrations may be falling, there are a variety of theories.

Swan suspects that one factor may be exposure to chemicals while in the womb, which could harm the normal development of males' reproductive systems.

"The mother's exposure to a number of chemicals can alter the reproductive tract of baby boys significantly," she says.

But Pacey questions that theory and worries about alarming pregnant women unnecessarily.

"There's a real danger here that researchers publish papers like this, that are then reported irresponsibly, that then lead to people getting really paranoid about what may or may not be happening," Pacey says.

The problems many couples encounter when they attempt to get pregnant could be avoided if they started trying just a few years earlier, Pacey says.

Swan acknowledges that other factors could be playing a role. The global obesity epidemic could be cutting sperms counts, for example.

"There's also stress, which is related to sperm count," she says. "So there are a number of factors which you could cluster under the heading of 'modern living' that could be playing a role in what we're seeing."

There wasn't enough data from non-Western countries to reach any conclusions about whether sperm counts are falling there, too, Swan says.

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Sperm Counts Plummet In Western Men, Study Finds - NPR

US Scientists Just Edited a Human Embryo for the First Time. (Yes, People Are Freaking Out.)Ben Birchall/Associated Press

For the first known time in the United States, scientists used a gene-editing technique called CRISPR to modify early-stage human embryos, according to a report published Wednesday in MIT Technology Review.

Since the development several years ago ofCRISPR, a tool that allows scientists to change sequences of DNA within a cell, scientists have speculated about its potential to free families of genetic disease or stop the spread of other diseases like malaria, among other possibilities. But the technology also raises major ethical questions.

Heres a quick rundown of the latest breakthroughand how it could change the way we think about humanreproduction and, well, humans themselves.

How did the experiment work?

According to MIT Technology Reviews report, a team of researchers at Oregon Health & Science University, led by geneticist Shoukhrat Mitalipov, used CRISPR to correct disease-causing genes in human embryos. Its not yet clear whether these were viable embryosembryos that could, theoretically, grow into humans.

A wide range of diseaseslike Huntingtons, sickle-cell anemia, and Tay-Sachs, for exampleare caused by mutations in genes. Its also not clear what genes Mitalipov and his team edited in their experiment. But regardless, it appears that their study was successful in a couple ways: First, they reportedly edited a greater number of embryos than scientists had in previous studies. Second, Mitalipov and his team claim they did so without causing as manyerrors as previous scientists.

CRISPR has been used to edit human embryos a few times before; Chinese scientists did it in March. But in prior experiments, scientists ran into problems when CRISPR edits were taken up only by some of the cells in an embryo. This is called mosaicism:it means that the child that develops from the embryo could still inherit the disease that scientists tried to edit away.

According to MITs report, Mitalipov reduced the occurrence of mosaicism and seemed to largely avoid off-target edits (another kind of CRISPR error, wherein scientists accidentally alter a gene other than the one they aim to change).

Why is this important?

A couple reasons. First, its the only known attempt to use CRISPR to edit human embryos in the United States. More on the legality of that below.

Second, if this attempt really was successful, its big news for people whose families carry genetic disease. In theory, using this technique, scientists could edit not just our offspring, but our offsprings offspring. This is called human germline editing. When scientists edit the DNA in an embryo, the changes will theoretically be inherited by each successive generation, permanently fixing the germlinethe genetic inheritanceof a family.

This seems ethically complex.

Right. The ethics and laws surrounding human germline editingare murky. Scientists in favor of human germlinemodification often argue that the techniquewill help us reduce the occurrence of genetic diseases.

But criticsdisagree.This is just not needed for preventing inheritable disease, said Marcy Darnovsky, Executive Director of the Center for Genetics and Society. There are [other techniques that] can already be used safely to prevent the births of children with serious genetic diseases in almost every case. One example of such a technique is preimplantation diagnosis, commonly referred to as PGD, which allows parents to screen embryos for certain disease-causing genes before implanting them through in vitro fertilization (IVF). But its not always effectiveif someone carries two copies of a defective gene, for example, all their embryos would carry that gene, as well.

Darnovsky also worries about safety. Despite whatever the claims are about safety, [like] no mosaicism, we still dont know if that would mean its safe to create a new human being and anyone who tried it would be taking an enormous and unacceptable risk with that future persons life.

Another concern: Right now, scientists aresupposed to stick to editing disease-causing genes. But the technology opens up the possibility of editing genes for enhancementallowing parents to edit for certain kinds of physical and behavioral characteristics in their children. Darnovsky worries that this would usher in an era of genetic discrimination. That would be layering new forms of inequality and discrimination onto the ones we already live with, she said.

Is this legal?

Probably.In 2015, Congress passed a law forbidding the Food and Drug Administration from reviewing applications for germline editing of human embryos, meaning no clinical trials can move forward with FDA funding. We dont yet knowhow Mitalipov funded his project, but assuming it was funded privately, its perfectly legal.

That wouldnt be the case in many other countries. The Center for Genetics and Society reports that over 40 countries, including most with established biotech sectors, have established legal prohibitions on germline modification for human reproduction. An international treaty also prohibits it. The United States has no such policy.

Whats next?

Well know more once the study is released, but its worth noting that in February of this year, the National Academy of Sciences and the National Academy published a report that said human germline editing could be permitted in the future. It outlined criteria for germline editing, recommending that it only be used for disease prevention. The authors of the report wrote that editing for the enhancement of human traits and capacities should not be allowed at this time. But the report didnt eliminate the possibility of editing for enhancement in the future.

Reactions to the report were mixed. Some experts, like Darnovsky, feel that human germline modification should not be done for any purpose. But in an interview with Science, Eric Lander, president and founding director of MIT and Harvards Broad Institute, a genomics research center, said he thought the report struck the right balance of optimism and caution. They want to put friction tape on the slope so the slope isnt slippery, Lander said. Whether and for how long the tape will hold is an open question.

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US Scientists Just Edited a Human Embryo for the First Time. (Yes, People Are Freaking Out.) - Mother Jones

The internet was abuzz about sperm last week, thanks to a new study that revealed an alarming drop in sperm counts for men in Western countries. Does this mean men are becoming infertile? Will we have problems having babies? Its not time to panic at least, not yet.

To be clear: the findings are worrisome. The researchers dug through thousands of studies from around the world, and found that for men living in Western countries sperm count has plummeted by between 50 and 60 percent since 1973. (Sperm count is the amount of sperm in the semen released in one ejaculation.) But that drop still leaves the average sperm count within a healthy, fertile range.

Does this mean were heading into a Children of Men type of situation? says John Amory, a professor and fertility expert at the University of Washington, who was not involved in the study. I doubt that very much, Im glad to say. Still, infertility can have a serious, and negative impact on peoples lives, and its important to nail down whether it is indeed on the rise, and why. It should be seen as a wake-up call, agrees Michael Eisenberg, a urologist at Stanford University, but not necessarily the end of days.

Scientists have been debating whether sperm count has been going down for about 25 years, ever since researchers in Denmark published a study in 1992 showing a 50 percent drop in sperm count between 1940 and 1990. Since the odds of fathering a child tend to increase with sperm quantity (although quality matters, too), a fall in sperm count could mean an overall drop in male fertility.

Some believed this frightening claim, suspecting that the ongoing decline might be triggered by smoking and exposures to pesticides or components of plastics leaching into our food and disrupting hormones. But others disputed it, believing that sperms disappearing act was a result of the different way scientists have counted and studied semen over the years.

Researchers led by Shanna Swan, a reproductive scientist at the Icahn School of Medicine at Mount Sinai, wanted to put the debate to rest. They screened more than 2,500 studies that reported sperm counts since 1973, filtering out papers that were too small, used dubious methods, or that specifically looked at infertile men. Instead, they picked studies that counted sperm the same way in semen collected from men who either didnt know if they were fertile, or who knew for certain that they were.

Then, they compared the results for men of the same age, from 1973 to 2011: the results show that for men living in Western countries, sperm concentrations and absolute sperm number have dropped between 52 and 59 percent. (Sperm concentration is the amount of sperm in a milliliter of semen; absolute sperm number is the amount in the total volume of a single ejaculation.) The findings were published in the journal Human Reproduction Update.

Heres why you shouldnt freak out: sperm concentration went from about 99 million sperm per milliliter of splooge in 1970 to 47 million sperm per milliliter in 2010. Theyre well within the fertile range, Amory says. Theyre falling from fertile to fertile. For reference, men can have a tougher time conceiving if sperm count falls below 40 million sperm per milliliter. The World Health Organization considers sperm concentrations less than 15 million sperm per milliliter of semen to be abnormally low.

But the study also didnt find any evidence that this decline was slowing down or stopping. That means that if sperm count continues to plummet, then we could see more men having problems conceiving. Its concerning its important we figure out whats going on, Swan says.

Thats because sperm counts are important for more than just fertility: sperm as the authors of the study put it are the tadpole-shaped canaries in the coal mine when it comes to health. Making sperm takes a complex series of events: it starts with producing hormones in the brain, which stimulates sperm production in the testicles. That sperm is then shuttled through a network of pipes, mixed with other ingredients, and shot out into the world. Its like a long chain of dominos, and if any have been knocked askew by, say, injury, infection, or any number of other unknown cases, they wont all fall neatly into place. So, if sperm counts are dropping, it could be a sign that something is damaging mens overall wellbeing. In fact, lower sperm counts have been linked to poorer health.

The current study couldnt get at exact causes. But its thought that if pregnant women are exposed to cigarette smoke, certain pesticides, and ingredients in plastics that can disrupt hormones, it may have long-term effects on a male fetuss future fertility. For adult men, obesity and smoking may also lower sperm counts although we dont know for certain.

This study is a start toward settling the debate, but there are still some caveats: men can produce different amounts of sperm even at different points throughout the day, for instance. And theres more to fertility than just number of sperm sperm wiggliness and shape, for example, are important, too.

To figure exactly whats going on, we need more research. If the Centers for Disease Control and Prevention were to actively collect data on semen over time, that could go a long way toward confirming a decline and helping researchers spot possible causes, Eisenberg says. Its concerning as a species, and it needs to be tracked more rigorously, he says. If its confirmed, we should be very concerned and find a way to stop it.

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Yes, sperm counts may be dropping, but it's not time to panic yet ... - The Verge