Is Sex for Reproduction About to Become Extinct?

A healthy fetus in utero at 22 weeks.
There are lots of great reasons we humans have sex. We mostly do it to pair bond, realize our primal urges, and feel good. Once in a while, we also do it to make babies. As the coming genetic revolution plays out, we'll still have sex for most of the same reasons we do today. But we'll increasingly not do it to procreate.
Protecting children from harm is one of the core responsibilities of parenting.
Most parents go to great lengths to protect their children from real and imagined harms. This begins with taking prenatal vitamins during pregnancy and extends to having children immunized and protected from exposures to various diseases and dangers. Most of us look askance for good reason at mothers who abuse controlled substances during their pregnancies or parents who choose to not immunize their children. Protecting children from harm is one of the core responsibilities of parenting.
In the United States today, up to two percent of babies are estimated to be born with rare genetic diseases caused by single gene mutations. Sickle cell disease, Tay-Sachs, and Huntington's disease are among the more well-known examples of these, but the list runs to the thousands. Many babies born with these disorders suffer terribly, some die young, and nearly all spend big chunks of their lives struggling through the medical system.
Increasingly, however, many of these single-gene mutation diseases and other chromosomal disorders like Down syndrome are being identified in non-invasive prenatal tests performed on expectant mothers at the end of their first trimester of pregnancy. Knowing the hardship that children born with these types of disorders will likely face, majorities of these women in countries around the world are choosing to terminate pregnancies once these diagnoses have been made. Whatever the justification and whatever anyone's views on the morality of abortion, these decisions are inherently excruciating.
A much smaller number of prospective mothers, however, are today getting this same information about their potential future children before their pregnancies even begin. By undergoing both in vitro fertilization (IVF) and preimplantation genetic testing (PGT), these women are able to know which of the eggs that have been surgically extracted from them and fertilized with their partner or donor's sperm will carry the dangerous mutations. The in vitro embryos with these disorders are simply not implanted in the expectant mother's womb.
It would be monstrous to assert that an existing person with a deadly disease has any less right to thrive than anyone else. But it would also be hard to make a case that parents should affirmatively choose to implant embryos carrying such a disease if given the option. If prospective parents are already today choosing not to implant certain embryos based on our preliminary understanding of disease risk, what will happen when this embryo selection is based on far more information than just a few thousand single gene mutation diseases?
Our ability and willingness to make genetic alterations to our future children will grow over time along with our knowledge and technological ability.
When the first human genome was sequenced in 2003, the race to uncover the mysteries of human genetics had only just begun. Although we still know very little about our genetics relative to the complexity of the genome and even less compared to the broader ecosystem of our biology, the progress toward greater understanding is astounding. Today, the number of single gene mutation diseases and relatively simple genetic traits that can be predicted meaningfully from genetic data alone is already significant.
In the not-distant future, this list will grow to include complex diseases and disease propensities, percentage probabilities of living a long and healthy life, and increasingly the genetic component of complex human attributes like height, IQ, and personality style. This predictive power of genetic analysis will funnel straight into our fertility clinics where prospective parents choosing embryos will be making ever more consequential decisions about the genetic components of the future lives, health, and capabilities of their children.
Our understanding of what the genes extracted from early stage pre-implanted embryos are telling us will be only one of the rocket boosters driving assisted reproduction forward. Another will be the ability to induce adult cells like skin and nucleated blood cells into stem cells and then turn those stem cells into egg progenitor cells and then ultimately eggs. This will not only eliminate the need for hormone treatments and surgery to extract human eggs but also make it easy and cheap to generate an unlimited number of eggs from a given woman.
The average woman has around fifteen eggs extracted during IVF but imagine what generating a thousand eggs will do to the range of possibilities that could be realized through pre-implantation embryo selection. Each of these thousand eggs would be the natural offspring of the two parents, but the variation between them would make it possible to choose the ones with the strongest expression of the genetic component of a particular desired trait – like those with the highest possible genetic IQ potential.
Another rocket booster will be the application of gene editing technologies like CRISPR to edit the genomes of pre-implanted embryos or of the sperm and eggs used to create them. Just this week, Chinese researchers announced they had used CRISPR to edit the CCR5 gene in the pre-implanted embryos of a pair of Chinese twins to make them immune to HIV, the first ever case of gene editing humans and a harbinger of our genetically engineered future. The astounding complexity of the human genome will put limits on our ability to safely make too many simultaneous genetic changes to human embryos, but our ability and willingness to make these types of alterations to our future children will grow over time along with our knowledge and technological ability.
With so much at stake, prospective parents will increasingly have a stark choice when determining how to conceive their children. If they go the traditional route of sex, they will experience both the benign wisdom and unfathomable cruelty of nature. If they use IVF and increasingly informed embryo selection, they will eliminate most single gene mutation diseases and likely increase their children's chances of living a longer and healthier life with more opportunity than their unenhanced peers. But the optimizing parents could also set up their children for misery if these children don't particularly enjoy what they have been optimized to become or see themselves as some type of freakish consumer product with emotions.
Conceiving though sex will come to be seen more and more like not immunizing your children is today, a perfectly natural choice that comes with a significant potential risk and expense.
But although there will be pros and cons on each side, the fight between conception through good old-fashioned sex and conception in the lab will ultimately not be fair. Differences and competition within and between societies will pressure parents and societies to adopt ever more aggressive forms of reproductive technology if they believe doing so will open possibilities and create opportunities for the next generations rather than close them.
Conception through sex will remain as useful as it has always been but lab conception will only get more advantageous. Over time, only zealots will choose to roll the dice of their future children's health and well-being rather than invest, like parents always have, in protecting their children from harm and helping optimize their life potential. Conceiving though sex will come to be seen more and more like not immunizing your children is today, a perfectly natural choice that comes with a significant potential risk and expense to yourself, your children, and your community.
As this future plays out, the genetics and assisted reproduction revolutions will raise enormous, thorny, and massively consequential questions about how we value and invest in diversity, equality, and our own essential humanity – questions we aren't remotely prepared to answer. But these revolutions are coming sooner than most of us understand or are prepared for so we had better get ready.
Because where this trail is ultimately heading goes well beyond sex and toward a fundamental transformation of our evolutionary process as a species – and that should be everybody's business.
Following the Footsteps of a 105-Year-Old Sprinter
No human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when he’s 105?
At the Louisiana Senior Games in November 2021, 105-year-old Julia Hawkins of Baton Rouge became the oldest woman to run 100 meters in an official competition, qualifying her for this year's National Senior Games. Perhaps not surprisingly, she was the only competitor in the race for people 105 and older. In this Leaps.org video, I interview Hawkins about her lifestyle habits over the decades. Then I ask Steven Austad, a pioneer in studying the mechanisms of aging, for his scientific insights into how those aspiring to become super-agers might follow in Hawkins' remarkable footsteps.
Following the Footsteps of a 105-Year-Old Sprinter
No human has run a distance of 100 meters faster than Usain Bolt’s lightning streak in 2009. He set this record at age 22. But what will Bolt’s time be when ...Matt Fuchs is the editor-in-chief of Leaps.org. He is also a contributing reporter to the Washington Post and has written for the New York Times, Time Magazine, WIRED and the Washington Post Magazine, among other outlets. Follow him on Twitter @fuchswriter.
Monkeypox produces more telltale signs than COVID-19. Scientists think that a “ring” vaccination strategy can be used when these signs appear to help with squelching the current outbreak of this disease.
A new virus has emerged and stoked fears of another pandemic: monkeypox. Since May 2022, it has been detected in 29 U.S. states, the District of Columbia, and Puerto Rico among international travelers and their close contacts. On a worldwide scale, as of June 30, there have been 5,323 cases in 52 countries.
The good news: An existing vaccine can go a long way toward preventing a catastrophic outbreak. Because monkeypox is a close relative of smallpox, the same vaccine can be used—and it is about 85 percent effective against the virus, according to the World Health Organization (WHO).
Also on the plus side, monkeypox is less contagious with milder illness than smallpox and, compared to COVID-19, produces more telltale signs. Scientists think that a “ring” vaccination strategy can be used when these signs appear to help with squelching this alarming outbreak.
How it’s transmitted
Monkeypox spreads between people primarily through direct contact with infectious sores, scabs, or bodily fluids. People also can catch it through respiratory secretions during prolonged, face-to-face contact, according to the Centers for Disease Control and Prevention (CDC).
As of June 30, there have been 396 documented monkeypox cases in the U.S., and the CDC has activated its Emergency Operations Center to mobilize additional personnel and resources. The U.S. Department of Health and Human Services is aiming to boost testing capacity and accessibility. No Americans have died from monkeypox during this outbreak but, during the COVID-19 pandemic (February 2020 to date), Africa has documented 12,141 cases and 363 deaths from monkeypox.
Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
A person infected with monkeypox typically has symptoms—for instance, fever and chills—in a contagious state, so knowing when to avoid close contact with others makes it easier to curtail than COVID-19.
Advantages of ring vaccination
For this reason, it’s feasible to vaccinate a “ring” of people around the infected individual rather than inoculating large swaths of the population. Ring vaccination proved effective in curbing the smallpox and Ebola outbreaks. As the monkeypox threat continues to loom, scientists view this as the best vaccine approach.
With many infections, “it normally would make sense to everyone to vaccinate more widely,” says Wesley C. Van Voorhis, a professor and director of the Center for Emerging and Re-emerging Infectious Diseases at the University of Washington School of Medicine in Seattle. However, “in this case, ring vaccination may be sufficient to contain the outbreak and also minimize the rare, but potentially serious side effects of the smallpox/monkeypox vaccine.”
There are two licensed smallpox vaccines in the United States: ACAM2000 (live Vaccina virus) and JYNNEOS (live virus non-replicating). The ACAM 2000, Van Voorhis says, is the old smallpox vaccine that, in rare instances, could spread diffusely within the body and cause heart problems, as well as severe rash in people with eczema or serious infection in immunocompromised patients.
To prevent organ damage, the current recommendation would be to use the JYNNEOS vaccine, says Phyllis Kanki, a professor of health sciences in the division of immunology and infectious diseases at the Harvard T.H. Chan School of Public Health. However, according to a report on the CDC’s website, people with immunocompromising conditions could have a higher risk of getting a severe case of monkeypox, despite being vaccinated, and “might be less likely to mount an effective response after any vaccination, including after JYNNEOS.”
In the late 1960s, the ring vaccination strategy became part of the WHO’s mission to globally eradicate smallpox, with the last known natural case described in Somalia in 1977. Ring vaccination can also refer to how a clinical trial is designed, as was the case in 2015, when this approach was used for researching the benefits of an investigational Ebola vaccine in Guinea, Kanki says.
“Since Monkeypox spreads by close contact and we have an effective vaccine, vaccinating high-risk individuals and their contacts may be a good strategy to limit transmission,” she says, adding that privacy is an important ethical principle that comes into play, as people with monkeypox would need to disclose their close contacts so that they could benefit from ring vaccination.
Rapid identification of cases and contacts—along with their cooperation—is essential for ring vaccination to be effective. Although mass vaccination also may work, the risk of infection to most of the population remains low while supply of the JYNNEOS vaccine is limited, says Stanley Deresinski, a clinical professor of medicine in the Infectious Disease Clinic at Stanford University School of Medicine.
Other strategies for preventing transmission
Ideally, the vaccine should be administered within four days of an exposure, but it’s recommended for up to 14 days. The WHO also advocates more widespread vaccination campaigns in the population segment with the most cases so far: men who engage in sex with other men.
The virus appears to be spreading in sexual networks, which differs from what was seen in previously reported outbreaks of monkeypox (outside of Africa), where risk was associated with travel to central or west Africa or various types of contact with individuals or animals from those locales. There is no evidence of transmission by food, but contaminated articles in the environment such as bedding are potential sources of the virus, Deresinski says.
Severe cases of monkeypox can occur, but “transmission of the virus requires close contact,” he says. “There is no evidence of aerosol transmission, as occurs with SARS-CoV-2, although it must be remembered that the smallpox virus, a close relative of monkeypox, was transmitted by aerosol.”
Deresinski points to the fact that in 2003, monkeypox was introduced into the U.S. through imports from Ghana of infected small mammals, such as Gambian giant rats, as pets. They infected prairie dogs, which also were sold as pets and, ultimately, this resulted in 37 confirmed transmissions to humans and 10 probable cases. A CDC investigation identified no cases of human-to-human transmission. Then, in 2021, a traveler flew from Nigeria to Dallas through Atlanta, developing skin lesions several days after arrival. Another CDC investigation yielded 223 contacts, although 85 percent were deemed to be at only minimal risk and the remainder at intermediate risk. No new cases were identified.
How much should we be worried
But how serious of a threat is monkeypox this time around? “Right now, the risk to the general public is very low,” says Scott Roberts, an assistant professor and associate medical director of infection prevention at Yale School of Medicine. “Monkeypox is spread through direct contact with infected skin lesions or through close contact for a prolonged period of time with an infected person. It is much less transmissible than COVID-19.”
The monkeypox incubation period—the time from infection until the onset of symptoms—is typically seven to 14 days but can range from five to 21 days, compared with only three days for the Omicron variant of COVID-19. With such a long incubation, there is a larger window to conduct contact tracing and vaccinate people before symptoms appear, which can prevent infection or lessen the severity.
But symptoms may present atypically or recognition may be delayed. “Ring vaccination works best with 100 percent adherence, and in the absence of a mandate, this is not achievable,” Roberts says.
At the outset of infection, symptoms include fever, chills, and fatigue. Several days later, a rash becomes noticeable, usually beginning on the face and spreading to other parts of the body, he says. The rash starts as flat lesions that raise and develop fluid, similar to manifestations of chickenpox. Once the rash scabs and falls off, a person is no longer contagious.
“It's an uncomfortable infection,” says Van Voorhis, the University of Washington School of Medicine professor. There may be swollen lymph nodes. Sores and rash are often limited to the genitals and areas around the mouth or rectum, suggesting intimate contact as the source of spread.
Symptoms of monkeypox usually last from two to four weeks. The WHO estimated that fatalities range from 3 to 6 percent. Although it’s believed to infect various animal species, including rodents and monkeys in west and central Africa, “the animal reservoir for the virus is unknown,” says Kanki, the Harvard T.H. Chan School of Public Health professor.
Too often, viruses originate in parts of the world that are too poor to grapple with them and may lack the resources to invest in vaccines and treatments. “This disease is endemic in central and west Africa, and it has basically been ignored until it jumped to the north and infected Europeans, Americans, and Canadians,” Van Voorhis says. “We have to do a better job in health care and prevention all over the world. This is the kind of thing that comes back to bite us.”