In an Italian court, a murderer has just had his sentence reduced because the judge agreed that the man’s genes predisposed him to violent behavior.
Abdelmalek Bayout, an Algerian immigrant to Italy, admitted to stabbing and killing Walter Felipe Novoa Perez, a Colombian, when the two men got in a fight over the kohl eye make-up that Bayout was wearing. At trial, the defense team argued that Bayout was mentally ill at the time of the murder; the judge agreed that his psychiatric condition was a mitigating factor, and gave him a reduced sentence of 9 years. But at an appeal hearing, Bayout’s lawyers argued that his sentence should be shortened further based not just on psychiatric evaluations, but also brain scans and genetic testing.
Emphysema and cystic fibrosis patients who need new lungs are faced with a life-threatening problem: more than 80 percent of donated lungs can’t be used—they’re inflamed and barely functional [Scientific American]. Transplanted lungs also fail at a much higher rate than other transplanted organs, as they’re more likely to be rejected by the recipient’s body. But a new procedure that makes use of gene therapy may soon double or triple the supply of undamaged donated lungs, and may also improve their function once transplanted.
In both pre- and post-transplant lungs, the problem is inflammation caused by insufficient amounts of an immune molecule called IL-10. Donated lungs are immediately chilled on ice, which destroys any IL-10 that may remain in the lungs, allowing substantial damage to occur before the organ can be implanted. And a lack of the molecule after transplantation increases the likelihood that inflammation will damage the organ and induce rejection [Los Angeles Times].
To get around these problems, the researchers first built a domed chamber where pig lungs were kept at body temperature with a steady flow of oxygen and nutrients moving through them. That arrangement alone prevented substantial damage to the lungs. Next, in the gene therapy stage, the researchers used a harmless virus to bring a gene that produces IL-10 into the lung cells.
For many rape cases, the only leads investigators have to follow are the clues spelled out by a DNA sample. If after years the DNA isn’t matched to a suspect the case goes cold and the victim never has closure. A few years ago, when there was still a statute of limitations for rape in New York City, prosecutors devised a clever way to side-step the ticking clock—they decided to simply indict the DNA profile. Since then, New York City prosecutors have secured 117 indictments of DNA samples in rape cases, linked 18 of those profiles to specific people, and obtained 13 convictions, either through trials or negotiated pleas. Five cases are pending [The New York Times].
Called John Doe DNA indictments, the strategy is also used in a handful of other states to help solve sex crimes, and its success has prompted officials to expand DNA indictments to other types of crimes. In New York, authorities are now collecting more DNA evidence from the scenes of everyday crimes. They hope to use DNA to help solve unsolved crimes from the past that are subject to a statute of limitations, like burglary, robbery or serial car theft [The New York Times]. Opponents of John Doe DNA indictments say the passage of time, along with fading memories and disappearing witnesses, hinders the defendant’s ability to mount a defense, and that old DNA samples are subject to depredation and mishandling. However New York officials counter by saying it’s irresponsible to ignore genetic evidence, especially with modern molecular biology tools.
Look into the future and see the women of tomorrow! A new study predicts that future women will be a tad shorter, heavier, and more fertile—that is, if the women who are currently most successful at producing children are any indication. The team studied 2238 women who had passed menopause and so completed their reproductive lives…[and] tested whether a woman’s height, weight, blood pressure, cholesterol or other traits correlated with the number of children she had borne. They controlled for changes due to social and cultural factors to calculate how strongly natural selection is shaping these traits [New Scientist].
Their results show that shorter, heavier women tend to have more children, as do women with lower blood pressure and cholesterol. If the mothers pass on these traits for 10 generations, the average woman in 2409 will be 2 centimetres shorter and 1 kilogram [about 2 pounds] heavier than she is today. She will bear her first child about 5 months earlier and enter menopause 10 months later [New Scientist]. A two-centimeter decrease over 400 years may be a modest change, but the researchers say it’s evolution in action. The study will be published in Proceedings of the National Academy of Sciences.
In very rare cases, the womb is a dangerous place for a developing fetus. Researchers have found that pregnant women can pass on cancer cells to their unborn babies, if those cancer cells carry a particular genetic mutation. The new study resolves a longstanding puzzle, because in theory any cancer cells that manage to cross the placenta into the baby’s bloodstream should be targeted for destruction by the child’s immune system. But there are records of 17 cases of a mother and baby appearing to share the same cancer – usually leukaemia or melanoma [BBC News].
In the study, which will be published in Proceedings of the National Academy of Sciences, researchers used a genetic “fingerprinting” technique to match the cancer cells found in a mother and baby. The case, involving a Japanese mother aged 28 and her daughter, revealed that both patients’ leukaemic cells carried the identical mutated cancer gene BCR-ABL1 even though the infant had not inherited this gene [The Times]. This meant that the child, who was diagnosed with cancer at the age of 11 months, could not have developed leukemia independently.
A new genetic analysis has confirmed that the “royal disease” suffered by the male descendants of Queen Victoria was in fact a rare type of hemophilia, the genetic disease marked by a deficiency in blood clotting. Queen Victoria had several sons that died from blood loss after seemingly minor injuries. The disease spread as her descendants married into other royal families across Europe, altering Western history.
Based on the sons’ reported symptoms, modern researchers had already hypothesized that the royals had hemophilia, but there was never any concrete evidence. Now, new DNA analysis on the bones of the last Russian royal family, the Romanovs, indicates the Royal disease was indeed hemophilia, a rare subtype known as hemophilia B [ScienceNOW Daily News]. The genotyping study was published in the journal Science.
To pinpoint the exact form of the disorder, the scientists extracted DNA from the skeletal remains of Queen Victoria’s great grandson Crown Prince Alexei of Russia’s Romanov family and decoded the genetic information. (The bones were found in 2007, and it was only earlier this year that they were confirmed to have belonged to the murdered prince, who was killed during the Russian revolution.) The new analysis discovered a mutation in a gene on the X chromosome that codes for the production of Factor IX, a substance that causes blood to clot [BBC News]. Since the mutation is on the X chromosome, the disease is carried by females but usually shows up only in male descendants, because they don’t have a second X chromosome with a working copy of the gene. Researchers say the finding of hemophilia B in the Romanov’s closes the case on the cause of “royal disease.”
When the Human Genome Project finished sequencing the first human genome earlier this decade, the price tag for the endeavor had reached almost $3 billion. Now, IBM has announced details of its effort to bring the cost of sequencing a person’s genome down to below $1,000–and the company says it could go as low as $100. While IBM is hardly the only company racing towards these goals, the company’s chip-based approach makes it a serious contender.
The company’s technique involves drilling tiny nanometer-size holes through computer-like silicon chips, then passing DNA strands through them to read the information contained in their genetic code. “We are merging computational biology and nanotechnology skills to produce something that will be very useful to the future of medicine” [Wired.com], says IBM scientist Gustavo Stolovitzky.
Stolovitzky says the work could usher in a new era of personalized medicine, in which patients routinely have their genomes scanned to help doctors make medical decisions. “Ultimately, it could improve the quality of medical care by identifying patients who will gain the greatest benefit from a particular medicine and those who are most at risk of adverse reaction,” said Stolovitzky [InformationWeek].
Scientists in the United Kingdom are outraged over a new program that seeks to determine asylum seekers’ nationalities through DNA and the isotopes present in their hair and fingernails. “Horrifying,” “naïve,” and “flawed” are among the adjectives geneticists and isotope specialists have used to describe the “Human Provenance pilot project,” launched quietly in mid-September by the U.K. Border Agency [Science Insider]. The experts say the tests simply aren’t accurate enough to pinpoint a person’s country of origin.
The program will be tried out on asylum seekers from the Horn of Africa, and will seek to establish whether applicants from Kenya or Ethiopia are masquerading as refugees from war-torn Somalia. Yet scientists say the Border Agency’s goals confuse ancestry or ethnicity with nationality. David Balding, a population geneticist at Imperial College London, notes that “genes don’t respect national borders, as many legitimate citizens are migrants or direct descendants of migrants, and many national borders split ethnic groups” [Science Insider].
Meat may be tasty, but many people object to way that chickens, cows, and other animals are treated at so-called “factory farms,” which produce massive amounts of edible flesh. So could animals that have been genetically engineered to not feel pain (or at least not be bothered by the sensation) offer a solution to an ethical dilemma posed by these meat factories?
That’s what one philosopher asked in a paper published in the journal Neuroethics, concluding that we have an ethical duty to consider the option. “If we can’t do away with factory farming, we should at least take steps to minimise the amount of suffering that is caused” [New Scientist] by practices such as de-beaking chickens without anesthesia, says author Adam Shriver. But because pain serves as an important warning sign, these so-called “pain-free” animals would still be able to sense pain–they just wouldn’t be bothered by it. Researchers seek ways to eliminate the suffering caused by pain without tampering with the physical sensation [New Scientist].
The pale-coated deer mouse that makes its home in Nebraska’s Sand Hills prairie has become a poster-mouse for evolution, based on results of a study published in Science.
The rodent typically has dark fur (bottom photo), but one Nebraska group of mice evolved to have lighter fur (top photo) after the Sand Hills formed 8,000 to 15,000 years ago. A lighter coat is advantageous because it allows the animal to blend in with its pale surroundings. But what’s more amazing is that before the formation of the Sand Hills, the deer mouse didn’t even possess the gene that controls coat color in the rodents.
The gene, which is known as Agouti, first appeared in deer mice in the Sand Hills about 4,000 years ago; after that, a mutation occurred that gave rise to the mouse’s sandy fur. “The light gene wasn’t in existence, so the mice had to “wait” until a particular mutation occurred and then selection had to act on that new mutation… It’s a two part process. First the mutation has to occur and second, selection has to increase its frequency” [BBC News], said co-author Hopi Hoekstra.
The remarkable diversity among dogs‘ coats–from the shaggy fur of a sheepdog to the sleek coat of a beagle, and everything in between–comes down to a mere three genes, according to a new report published in Science. The broad genetic study determined that one gene controls hair length and softness, another determines whether the hair is straight or curly, and a third controls the pattern in which hair grows, so that dogs with a particular version have wiry hair and moustaches and long facial details known to breeders as “furnishings”…. The combinations in which these genes are inherited then determine a dog’s overall look [The Times].
To reach these conclusions, the researchers first looked at the genetic differences within single breeds that have more than one coat type. Purebred dogs are particularly suited for this kind of study, Dr. Ostrander said, because they have been selectively bred to segregate traits — there are long- and short-haired dachshunds, for example [The New York Times]. By analyzing the genomes of two dachshunds with different types of coats, the researchers were able to determine which gene was linked to the variation in hair length. Similar studies revealed the other two genes.
These cute little macaque monkeys may have gotten their fluffy brown fur from their father, their big eyes from their mother, and their good health from… their other mother.
The scientific advance heralded in a new paper in Nature is essentially procedural: Researchers have figured out how to make an embryo that does not carry the mitochondrial DNA of its mother but that of another female instead, which could prevent diseases that are caused by inherited defects in this genetic material. But the study’s immediate impact comes from the ethical questions it raises. “With this you have potentially three genetic parents,” said [bioethics expert] David Magnus…. “This will create the potential for legal and social conflicts.” [Washington Post].
While more than 99 percent of an embryo’s DNA comes from the union of a sperm cell with the nucleus inside a female egg, the other 1 percent is found in other structures outside the egg’s nucleus–the mitochondria, the cellular power plants that produce chemical energy. This mitochondrial DNA is inherited only from the mother, but in the new study on rhesus macaques researchers monkeyed with that biological truism.
When 18-year-old Caster Semenya blew past the competition in the women’s 800-meter race at the World Athletics Championships in Berlin this week, she got more than a gold medal. The South African athlete ran straight into a controversy about both the nature of gender and hers in particular. Some other runners contend that Semenya, with her stereotypically masculine build, is really a man, while the more temperate governing body, the International Association of Athletic Federations, says it needs to determine if she has male characteristics that give her an unfair advantage. To settle the question, the IAAF has ordered tests by a gynecologist, an endocrinologist, a gender expert, and a psychologist.
Gender expert Richard Auchus says assigning sex was hardly as easy as sizing someone up visually…. “For 99 percent of the population it’s easy to determine…. But one percent of the population have conditions that make it not so straightforward” [The New York Times]. In the 1960s, athletic federations began testing athletes by scraping cells from their mouths and testing them for a pair of X chromosomes, which typically establishes a person’s sex as female (as opposed to the XY chromosomes typically carried by males). But the tests were halted in the 1990s as critics pointed out that there are medical conditions that lead individuals with two X chromosomes to develop masculine characteristics, and others that mean individuals with one X and one Y chromosome never develop masculine characteristics. Some other individuals also exist outside the usual sexes of XX females and XY males; these may include males who are XXY, further confusing the tests [Nature News].
The discovery of a pair of genes that prompt rice plants to grow extra-tall when submerged in water could potentially lead to new hardier varieties of rice that yield food even in flooded conditions, and could help out farmers in flood-prone nations like Thailand and Cambodia, according to a study published in Nature.
Researchers discovered a pair of genes known as SNORKEL, which spurs growth among the plants when they are completely submerged, allowing the plants to survive by keeping their leaf tops above the water. As water levels rise, accumulation of the plant hormone ethylene activates the SNORKEL genes, making stem growth more rapid. When the researchers introduced the genes into rice that does not normally survive in deep water, they were able to rescue the plants from drowning [AP].
In an announcement certain to fuel conspiracy theories and science fiction stories alike, Israeli scientists revealed that they can fabricate blood and saliva samples that don’t contain DNA from the person who donated the samples, but rather hold the genetic code of an unrelated person. Theoretically, such samples could end up being used as false DNA evidence. Says lead researcher Dan Frumkin: “You can just engineer a crime scene…. Any biology undergraduate could perform this” [The New York Times]. While it might be easier for a shadowy crime scene-fixer to plant a stray hair or cigarette butt than to cook up a misleading batch of blood or saliva, researchers say that they can imagine scenarios in which blood or saliva would be more convincing.
Frumkin and his colleagues at the private company Nucleix used two different methods to create the false samples. In the first, the researchers take a tiny DNA sample from an individual’s hair or spit, and use a process called DNA amplification to increase the sample size. The researchers then took blood from another individual and put it through a centrifuge to remove the DNA-carrying white blood cells, leaving behind the red blood cells, which don’t carry DNA. They then added the applified DNA to the blood sample, et voila! When this engineered blood sample was sent to a leading forensic lab, the analysis detected the DNA of only the original individual, and saw nothing amiss.
But, don’t worry, like a hacker taking down servers to sell cyber security services, Nucleix has a fix: a system that can detect the difference between natural and manufactured DNA. It looks for a lack of methylation; an addition of methyl groups to DNA occurs naturally in genetic code, but it isn’t found in Nucleix’s manipulated DNA [Scientific American].
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In an Italian court, a murderer has just had his sentence reduced because the judge agreed that the man’s genes predisposed him to violent behavior.
For many rape cases, the only leads investigators have to follow are the clues spelled out by a DNA sample. If after years the DNA isn’t matched to a suspect the case goes cold and the victim never has closure. A few years ago, when there was still a statute of limitations for rape in New York City, prosecutors devised a clever way to side-step the ticking clock—they decided to simply indict the DNA profile. Since then, New York City
Look into the future and see the women of tomorrow! A new 
In very rare cases, the womb is a dangerous place for a developing fetus. Researchers have found that pregnant women can pass on 
A new 
When the Human Genome Project finished sequencing the first human genome earlier this decade, the price tag for the endeavor had reached almost $3 billion. Now, 
Scientists in the United Kingdom are outraged over a new program that seeks to determine asylum seekers’ nationalities through DNA and the isotopes present in their hair and fingernails. 
Meat may be tasty, but many people object to way that chickens, cows, and other animals are treated at so-called “factory farms,” which produce massive amounts of edible flesh. So could animals that have been genetically engineered to not feel pain (or at least not be bothered by the sensation) offer a solution to an ethical dilemma posed by these meat factories?
The pale-coated deer mouse that makes its home in Nebraska’s Sand Hills prairie has become a poster-mouse for 
The remarkable diversity among 
These cute little macaque monkeys may have gotten their fluffy brown fur from their father, their big eyes from their mother, and their good health from… their other mother.
When 18-year-old Caster Semenya blew past the competition in the women’s 800-meter 
In an announcement certain to fuel conspiracy theories and science fiction stories alike, Israeli scientists revealed that they can fabricate blood and saliva samples that don’t contain 
