The latest step toward engineering artificial life.
(For discussions of the latest topics, check out the new Human Nature Fray.)
Scientists derived embryonic stem cells from human eggs without fertilization or cloning. This is a variant of parthenogenesis, which has produced lizards, sharks, and turkeys, but has never produced a live mammal. Scientists' spin: Now we can make stem cells without medically troublesome "animal-derived components" and without ethically troublesome human embryos. Catholic critique: "If these grow as organized embryos for the first few days and then arrest, they may just be very short-lived human beings." Even a leading scientist calls them "a different kind of embryo." (For Human Nature's take on parthenogenesis and virgin births, click here.)
Researchers took a big step toward creating synthetic life. They transplanted one microorganism's genome into another, completely changing its identity and behavior. The goal down the road is to create a genome and then do the transplant, so the new organism will be man-made. Scientists' spins: 1) We can make bacteria that produce fuel and fight global warming! 2) Don't worry, the bacteria we're using don't cause disease, and we can engineer them to self-destruct if they escape the lab. Rebuttal: Somebody else could use the same techniques to engineer bacteria that do cause disease or wreak some other kind of havoc. (To debate the wisdom of making synthetic life, click here.)
Gays and ex-gays are fighting over converting people from homosexuality. Around 1,000 people are expected at this week's gathering of Exodus International, a group that advocates conversion. Ex-ex-gays—former conversion advocates who have gone back to accepting their homosexuality—are staging a rival "ex-gay survivor" conference. Ex-ex-gays' messages: 1) "God's love and forgiveness does indeed change people. It changed me. It just didn't make me straight." 2) Homosexuality is so "integral" that trying to squeeze it out of people is more likely to cause shame, isolation, and possibly suicide than to change their orientation. Exodus president's rebuttal: 1) Agreed, orientation "isn't a light switch that you can switch on and off." But 2) some people, including me, have overcome it, and 3) "giving people options isn't dangerous." (For recent updates on conservatives acknowledging homosexuality as innate, click here and here. For gay sheep and the biology of homosexuality, click here and here. For the pope's doctrine on struggling with homosexuality, click here. To debate conversion from homosexuality, click here.)
The Catholic bishops of England and Wales demanded human rights for "interspecies embryos." Scientists are creating such embryos for medical research; the British government is proposing to authorize their creation but to forbid them from being transferred to a human womb or kept alive beyond 14 days. Bishops' testimony: 1) "Interspecies embryos" should be treated like human embryos. 2) "At very least, embryos with a preponderance of human genes should be assumed to be embryonic human beings." 3) "It should not be a crime to transfer them … to the body of the woman providing the ovum, in cases where a human ovum has been used to create them. Such a woman is the genetic mother, or partial mother, of the embryo; should she have a change of heart and wish to carry her child to term, she should not be prevented from doing so." Scientists' response: No human ovum is involved when we put a human cell nucleus in an animal egg. Rebuttal: That's not the only kind of interspecies embryo the legislation authorizes. (For Human Nature's take on the proliferation of interspecies creatures, click here. To discuss their rights, click here.)
Data from anew U.S. government sex survey (of adults aged 20 to 59): Percentage who are virgins: 4. Percentage who were still virgins on their 21st birthday: 15. Percentage of women who have had only one sex partner (or none): 25. Percentage of men who have had only one sex partner (or none): 17. Women's median number of sex partners: 3.7. Men's median number: 6.8. Conservative view: People aren't complying with abstinence and monogamy. Liberal view: Abstinence and monogamy aren't complying with human nature. (For Human Nature's take on the rate of anal sex in a previous U.S. survey, click here. To debate the practicality of abstinence, click here.)
Four babies from a new batch of U.S. sextuplets have died. The two survivors are in critical condition. Because they were multiples, the babies were born at 22 weeks, barely halfway through the normal period of gestation. Meanwhile, all sextuplets from a near-simultaneous batch are alive, but they'll be in intensive care for two months, and the mother nearly died of heart failure after delivery. Both women took ovulation-boosting drugs; both refused "reduction," i.e., abortion, of some of the fetuses to save others. Criticisms: 1) They shouldn't have taken the drugs. 2) They should have agreed to reduction. 3) The media should stop cooing over multiple births. Parents' explanation for refusing reduction: "Each one of them is a miracle given to us by God." (To discuss the ethics of aborting extra fetuses, click here.)
Another shark fetus has developed in a tank with no apparent father. No male of the shark's species was in the tank. The fetus was found because its mother died; otherwise, attendants think it would quickly have been eaten and thus would never have been discovered. Implication: Births to sharks with no apparent fathers may happen more often than we realize, because when there's no male around, we don't look for offspring. Kinky theory: It's another case of parthenogenesis, i.e., virgin birth. Kinkier theory: It's impregnation by a shark of another species—"the first known shark hybrid." DNA testing will resolve the question. (For Human Nature's take on parthenogenesis in sharks and other animals, click here. To discuss virgin births, click here.)
A study suggests conservative Muslim dress codes are causing vitamin D deficiency by depriving women of sunlight. Researchers "previously found a high prevalence of vitaminD deficiency … in Arab andEast Indian women residing in the United Arab Emirates." In a follow-up study of 178 UAE women, "Many dressed to cover their whole bodies, including their hands and faces, while outside of their homes. Only two of the women, one in each group, were not vitamin D deficient." After three months of supplements, only 30 percent of the women who finished the study achieved recommended levels of vitamin D. Researchers' conclusion: These women need higher doses of vitamin D. Human Nature's conclusion: They need lower doses of fundamentalism. (For Human Nature's take on tanning, click here. To debate tanning, vitamin D, and skin cancer, click here.)
The International Association of Athletics Federations will let a sprinter with prosthetic legs race in the Olympics if he qualifies. His legs were amputated below the knees in infancy due to a birth defect. He has replaced them with carbon-fiber blades. Three months ago, an IAAF ban on "any technical device that incorporates springs, wheels or any other element that provides the user with an advantage" was interpreted to include his blades, but the IAAF now says the rule doesn't apply to him since "it was aimed at sophisticated gadgets manufacturers add to the shoes of top athletes." Feel-good spin: Now he can race in the Olympics! Cynical view: Now he won't qualify. (For a previous update on this case, click here. For Human Nature's takes on athletic enhancement, click here and here. To debate the rules of athletic enhancement, click here.)
A U.S. surgeon removed a gall bladder through the patient's mouth. The procedure had been done previously in Brazil, but this is the first time it has been done in the United States. Method: Thread the instruments through the esophagus, then use them to snip a hole in the stomach, cut out the gall bladder, and pull it back out through the mouth. Rationale: less pain, scarring, and recovery time than you'd get from an incision in your abdominal wall. The surgeon says this method could turn gall-bladder surgery into a doctor's-office procedure. Doctors had already removed a woman's gall bladder through her vagina. Why switch to the mouth? Surgeon's answer: "Since only half the population has vaginas we were looking for a more universal platform." (For previous updates on natural orifice surgery, click here, here, and here.)
Latest Human Nature columns: 1) The reunion of man and beast. 2) The spread of virgin births. 3) The abolition of menstruation. 4) The chess match of man and machine. 5) Ultrasound and the future of abortion. 6) The global market in human organs. 7) The evolution of brains and morals. 8) Machines that read your mind. 9) Invasion of the naked body scanners. 10) The future of pain-beaming weapons.
Will Saletan covers science, technology, and politics for Slate and says a lot of things that get him in trouble.
Photograph of nun on Slate's home page by Digital Vision.