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In the western world, marriage between first cousins is labeled incest or inbreeding, and in the United States the practice is banned or restricted in 31 states. But a new essay argues that such laws are based on an outdated notion of the genetic risks involved in cousins marrying and reproducing. [T]hose laws “seem ill-advised” and “should be repealed,” a geneticist and medical historian write…. “Neither the scientific nor social assumptions that informed them are any longer defensible” [Scientific American].

First cousins share about an eighth of their genes, and are therefore more likely to receive two copies of some recessive gene that poses health problems. Scientists had assumed that the children of first cousins would therefore be more likely to be born with birth defects. But coauthor Hamish Spencer writes that the risk of congenital defects is about 2 per cent higher than average for babies born to first-cousin marriages – with the infant mortality about 4.4 per cent higher – which is on a par with the risk to babies born to women over 40. “Women over the age of 40 have a similar risk of having children with birth defects and no one is suggesting they should be prevented from reproducing,” said Professor Spencer [The Independent].

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Researchers had high hopes for Cedric the Tasmanian devil: They believed he was the first member of the species to be immune to the deadly facial cancer that is rapidly devastating devil populations. Now, in a major setback, Cedric has grown two small tumors and researchers are back to square one. Many experts believe that the infectious cancer, called devil facial tumor disease, could drive the species to extinction within 20 years if it goes unchecked.

Cedric was captured in western Tasmania last year, along with his half-brother, Clinky. Both were injected with dead tumours by scientists. Clinky produced no antibodies, but Cedric did, and appeared to have built-in defences against the illness [BBC News]. However, the next step yielded worse results. Researchers injected two live strains of the disease into Cedric’s cheek in an attempt to prove his immunity, but two small tumors grew at the injection sites. The tumors were surgically removed last week, and while Cedric is expected to make a full recovery, his love life has been put on hold by the researchers. They were trying to get him to mate so he would pass on his genes. Now they’re unsure if Cedric is naturally immune to the disease [ABC News].

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Health care workers who have a moral or religious objection to a medical procedure can’t be punished or discriminated against if they refuse to perform it, according to a sweeping new rule (pdf) announced by the Bush administration yesterday. The right-to-refuse rule includes abortion, but [the department of Health and Human Services] said it extends to other aspects of health care where moral concerns could arise, including birth control, emergency contraception, in vitro fertilization, stem cell research or assisted suicide. The rule will take effect the day before President George W. Bush leaves office [Baltimore Sun]. If a hospital, clinic, pharmacy, health plan, or any other medical establishment refuses to follow the new law it will forfeit all federal funding.

The rule has been eagerly anticipated by anti-abortion activists, but has raised furious objections from family planning groups and much of the medical establishment (groups such as the American Medical Association and the American Hospital Association opposed the regulation). Officials at hospitals and clinics predicted the regulation will cause widespread disruptions, forcing family planning centers and fertility clinics, for example, to hire employees even if they oppose abortions or in vitro fertilization procedures that can destroy embryos. “It is going to cause chaos among providers across the country,” said Cecile Richards of the Planned Parenthood Federation of America. The regulation could also make it difficult for states to enforce laws such as those requiring hospitals to offer rape victims the morning-after pill, experts said [Washington Post].

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Don’t let their fierce looks fool you: Some male carnivorous dinosaurs were actually devoted dads, researchers say. A new study examined the bones of three species of dinosaurs found sitting on fossilized egg clutches and declared that in these species, it was the males who sat on the nests and cared for the young. The three types of dinosaurs, Troodon, Oviraptor and Citipati, lived roughly 75 million years ago and were theropods — the primarily meat-eating group that also includes monstrous beasts like Tyrannosaurus rex and Giganotosaurus [Reuters].

The new findings upend some notions of dinosaur family life, and also suggest that birds, which are believed to have evolved from small, feathered dinosaurs, may have inherited this behavioral trait. Study coauthor Frankie Jackson says the study “sheds light on the origins of parental care systems in birds.” … Males protect or support offspring in more than 90 percent of bird species — a distinctly rare attribute in the animal world. In mammals, males provide parental care in 5 percent of species, and it’s even rarer in reptiles [Washington Post].

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The Vatican has issued new ethical guidelines in response to the biomedical advances of the last 20 years, and has come down hard on assisted reproduction technologies and genetic engineering. The document, Dignitas Personae (which translates as “human dignity”), reaffirm the church’s opposition to in vitro fertilization. It also tells Catholics that the church also doesn’t condone “adopting” leftover fertilized embryos from fertility clinics, and frowns upon the genetic testing of embryos before implantation, which could lead to the embryo being discarded. The Vatican says these techniques violate the principles that every human life — even an embryo — is sacred, and that babies should be conceived only through intercourse by a married couple [The New York Times].

These instructions stem from two fundamental theological principles: that life begins at conception and that the origin of human life is the “fruit of marriage.” … The document now makes clear that the morning-after pill, RU-486, and intrauterine devices (IUDs), which either intercept the embryo before implantation or eliminate it after implantation, “fall within the sin of abortion” [Scientific American]. The guidelines may come as a surprise to many Catholics who don’t realize that the church takes such a strict stance on medical technologies like in vitro fertilization that are often seen as routine and beneficial.

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Even after people struggling with infertility have found a happy ending with in vitro fertilization, another complicated dilemma remains: what to do with extra fertilized embryos created during treatment. A new study found that more than 400,000 of these embryos are currently chilling in the freezers of fertility clinics around the country; while some of those are being stored for women who want more children, many others are being kept on ice because women have qualms about disposing of them. And while some women are willing to donate their embryos to research, that option frequently isn’t offered.

Ethical and personal considerations have led some people to a stalemate. For nearly 15 years, Kim and Walt Best have been paying about $200 a year to keep nine embryos stored in a freezer at a fertility clinic at Duke University — embryos that they no longer need, because they are finished having children but that Ms. Best cannot bear to destroy, donate for research or give away to another couple…. “There is no easy answer,” said Ms. Best, a nurse. “I can’t look at my twins and not wonder sometimes what the other nine would be like” [The New York Times].

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Poor Lonesome George: Although he may have found a mate, researchers say he is still being denied the joys of fatherhood. George is thought to be the last representative of a tortoise subspecies from the Galapagos Island of Pinta, and researchers rejoiced this summer when he appeared to father a batch of eggs. But earlier this week a spokesperson for the Galapagos National Park announced that 80 percent of the eggs do not appear to be viable.

The excitement began this summer when two female tortoises exhibited surprising behavior. The females, who have shared George’s enclosure at the Charles Darwin Research Station on the central island of Santa Cruz for almost 20 years, are of a different but closely related species. After decades of reproductive reticence, they stunned scientists during the summer by building nests and filling them with eggs for the first time [Nature News]. Researchers quickly removed the 16 eggs from the nests and installed them in an artificial incubator, although three of those eggs were thought to have already deteriorated.

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Dosing menopausal women with testosterone may be the key to helping those with low libidos get back in the mood, according to a new study. Proctor & Gamble Pharmaceuticals has published the results of a new trial of their testosterone patch, called Intrinsa, and say the results are encouraging for frustrated older women seeking a “Viagra for women.” However, nagging safety concerns are likely to keep the drug off the market in the United States for some time to come (although the drug is already on sale in Europe): During the new study, four of the test subjects using the patch developed breast cancer.

The 52-week study included 814 women with sexual desire disorder, characterized by troublesome low sexual desire or function…. The women were asked to keep sexual encounter diaries, and researchers used other established measures to assess sexual response during the six-month evaluation phase of the study. They found that compared to placebo users, the women who used the 300 microgram patch reported significant improvements in sexual functioning, including desire, arousal, orgasm, and pleasure [WebMD].

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Several rare varieties of staghorn coral have begun mating across species lines and are creating surprisingly robust hybrids, according to a new study; researchers believe the unusual step is an effort to adapt to changing ocean conditions and avoid extinction. The findings are an unexpected piece of promising news about coral reefs, which usually make the headlines for their potential fate as one of the first victims of global warming.

Coral reefs around the world are under pressure from pollution and gradually warming oceans, and researchers have worried that rare species are particularly vulnerable to extinction. But in the case of these staghorns, the new study shows that when faced with a shortage of mates of their own kind, these rare corals have cast a wider net and started cross-breeding with other coral species, producing hybrids. “It pushes the boundaries of our traditional understanding of species,” said a researcher, Zoe Richards. “They are being a little promiscuous” [Sydney Morning-Herald].

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Cannibalistic female spiders who chow down on males do so to give their fertilized eggs a developmental boost, a new study suggests. Researchers found that those Mediterranean tarantulas who ate their suitors produced more offspring, and those spiderlings were stronger and bigger than the offspring of tarantulas that had stuck to more natural prey.

The study turned up several surprises. The researchers watched the tarantulas’ behavior in their natural environments, and saw that the female spiders didn’t eat their mates–instead they waited until after they had mated, and then devoured the next unlucky suitor who came along. Some other studies have suggested that males may sacrifice themselves for the sake of their offspring, but this study showed that, at least in this species of spider, the males are purely unlucky victims and only the babies benefit [Reuters].

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For many people diagnosed with a sexually transmitted disease, notifying past sexual partners of their health risk is a task that’s just too humiliating to face. That’s why the inSPOT service was created four years ago, a new report explains. With just a few clicks, people can send an anonymous (or signed) e-card to past partners, letting them know that a trip to the doctor is in order. The email includes links to health clinics and STD information, and no information about the sender or the recipient is collected.

The project began when Dr. Jeffrey Klausner of the San Francisco Department of Public Health got together with the tech-savvy nonprofit Internet Sexuality Information Services (ISIS), and brainstormed ideas for a response to an STD outbreak in the gay community. “In 1999, I discovered an outbreak of syphilis related to an AOL chatroom,” Klausner said. Just a year before, San Francisco had eight cases of syphilis a year. By the end of 2004, Klausner said, the city had 550 reported cases. After tracing the outbreaks to the chatroom, Klausner and colleagues at I.S.I.S. Inc decided to use the same type of communication that facilitated the hook-ups to help resolve the situation [ABC News].

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A new study of the prairie vole, a rodent species famed for its monogamous ways, has shown that the vole’s brain chemistry changes when its mate is taken away, and that it loses some of its vim and vigor. Researchers compared the behavior of males who were separated from either their mates or their siblings, and found that those voles who had lost their loyal mates were passive and unresponsive–maybe even depressed.

Prairie voles are one of the few mammals that are generally monogamous; the mates form life-long bonds and rear their pups together. In the new study, researchers subjected all the male voles to stress tests, like dunking them in basins of water and holding them suspended by their tails, and found that the voles whose mates had been spirited away put up less struggle. In the water, for example, they floated listlessly instead of paddling for their lives. These voles “basically were passive — they gave up,” [study coauthor Larry] Young said. “I would be hesitant to say that these animals were depressed, but their behavior is reminiscent of what you would see in a depressed person” [HealthDay News].

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A female blacktip shark in a Virginia aquarium got pregnant despite the fact that no male blacktip sharks shared her tank in her eight years of residency, researchers say. This is the second documented case of asexual reproduction, or parthenogenesis, among sharks; the first example of a shark “virgin birth” occurred with a hammerhead shark in a Nebraska zoo. The new findings suggest that the previous event wasn’t a marine miracle. “This first case was no fluke,” Demian Chapman, a shark scientist and lead author of the second study, said in a statement. “It is quite possible that this is something female sharks of many species can do on occasion” [AP].

Now scientists are debating whether asexual reproduction is a backup method for female sharks that can’t find a mate, or whether the pregnancy was a developmental aberration that occurs from time to time. Chapman argues for the first camp: “The reason this has happened in captivity isn’t because there’s a change in their reproductive biology,” he explains. “It is more likely to happen if female sharks aren’t having enough dates,” he says. “These females did it because they were in captivity and ovulating” [Science News].

But others say that since the shark didn’t produce a normal litter of four to six pups, the pregnancy could have been an anomaly. “The fact that only one shark embryo was formed may suggest that this is more a case of an egg developmental aberration rather than a physiological response to the lack of a mate,” said [shark expert Robert] Hueter [National Geographic News].

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Researchers have found a way to turn cells from human testes into adult stem cells, raising the possibility that men could eventually have spare cells from their own testicles converted into other kinds of tissue for medical treatments and bodily “repairs.” Lead researcher Thomas Skutella harvested spermatogonial cells, which normally mature into sperm, from men and used a series of chemicals to turn them into various cell types…. “We made them into skin, structures of the gut, cartilage, bone, muscle and neurons,” says Skutella [New Scientist].

The achievement is of particular interest because it avoids the ethical quandaries involved in using embryonic stem cells, which require destroying a human embryo. Using testicular cells isn’t the only promising method that avoids embryos; there have been impressive experiments in reprogramming ordinary body cells into stem cells by slipping certain genes into them. The new findings and the reprogrammed cells — which still have technical hurdles — “take some pressure off the stem cell issue,” said White House science adviser Jack Marburger [AP].

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Two separate groups of researchers have developed a non-invasive test for Down syndrome, using only a blood sample from the pregnant woman to examine the fetus’ DNA. While the genetic tests are still in clinical trials, experts are hailing the achievement as significant because current prenatal tests like amniocentesis require inserting a needle in the uterus, and carry a risk of miscarriage.

A biotechnology company called Sequenom says it will begin selling its test next June, while researchers from Stanford, who just published their results in the Proceedings of the National Academy of Sciences, are still planning a large-scale clinical trial. Some experts say that the results are somewhat preliminary, and should be viewed cautiously: The Stanford test has been tried on only 18 blood samples. Sequenom has tried its test on only about 400 samples and has not yet published its results in peer-reviewed journals. Still, both tests have perfect records so far: no false negatives or false positives. “This is quite simply a major step forward, if it works at all like we expect it might,” [says Down Syndrome expert] Jacob A. Canick [The New York Times].

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