For two squirrel monkeys nicknamed Dalton and Sam, life has gotten a lot more colorful. Researchers used gene therapy to correct the color blindness of the two adult monkeys, giving them the ability to distinguish between red and green for the first time. The fascinating accomplishment suggests that scientists may someday be able to cure other kinds of blindness in humans. And because the treated monkeys were “middle aged”, it challenges the assumption that gene therapies cannot work in adults because their brain connections are too set in their ways to change beneficially [New Scientist].
The field of gene therapy, in which a malfunctioning gene in a patient’s body is replaced with a functional one, fell into disarray one decade ago following the death of an 18-year-old in a clinical trial. But since then scientists have regrouped, using animal studies to probe the technique’s safety. Last year, researchers progressed to the point of safety trials in humans for the treatment of one rare eye condition called Leber congenital amaurosis, and were able to dramatically improve the patients’ sight. Those results were stunning, but they were also achieved in children, whose still-growing brains can rewire themselves on the fly in response to new sources of visual stimuli [Wired.com].
In the new study, published in Nature, the researchers used a type of squirrel monkey in which the males lack a visual pigment called L-opsin. Its absence renders the monkeys color-blind, unable to distinguish reds and green. Most of the females, on the other hand, see in full color. So the scientists got to wondering: what would happen if they gave a boy squirrel monkey the same opsin that girls have [Scientific American]. They used a harmless virus to ferry in the gene that makes opsin, injecting the virus behind the monkeys’ retinas.
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].
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.
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].
Scientists have created genetically engineered corn plants that resist a root-destroying larvae by emitting a chemical call for help, summoning a parasite that preys on the larvae.
The larvae of the western corn rootworm (actually a beetle) is considered the most destructive corn pest in the United States and plagues parts of Europe as well. Known as the billion-dollar bug, the rootworm is said to be responsible for crop damage and pest-control spending valued at more than nine figures [National Geographic News]. To fight the larvae without the use of synthetic pesticides, researchers created corn plants that release a chemical compound into the soil, which calls forth parasitic nematodes to come and infest the beetle larvae.
Changes in an organism’s genome that once took years to make in a lab can now be done in a fraction of the time, thanks to a new method of genome engineering. “This technique allows us to do some amount of rapid evolution” [New Scientist], says lead researcher Harris Wang.
In the experiment, the scientists used a technique called Multiplex Automated Genome Engineering, or MAGE, to program E. coli bacteria to produce five times as much of an antioxidant called lycopene than normal. In addition, using the process, which grafts pieces of synthetic DNA into the genomes of dividing cells, researchers generated 15 billion different genomic patterns in just three days. The process would normally take years, and could eventually be used to produce industrial chemicals, drugs, fuel and anything else that comes out of bacteria [Wired.com]. The process is significantly faster than previous techniques, in which scientists had to modify genes by changing bases one by one, for example, or by cutting genes from one genome and gluing them into another, modifying and inserting them one at a time.
From reprogrammed skin cells, scientists have made live mice.
The accomplishment is the latest step forward in the exciting new field of reprogrammed cells, which may offer an alternative to embryonic stem cells…. [It's] the most definitive evidence yet that the technique could help sidestep many of the explosive ethical issues engulfing the controversial field [Washington Post]. Two new studies describe the process, and one team of researchers reports producing 27 live mice. While there were abnormalities and unusual deaths with some of the first generation of mice, [the] team produced enough normal mice this way to create hundreds of second and third generation mice [AP].
It was only three years ago that Japanese stem cell researchers found a way to reprogram ordinary skin cells to behave like embryonic stem cells, which are thought to hold vast potential for medical research because they can develop into any kind of body tissue–from heart cells to toenail cells. But researchers didn’t know if the reprogrammed adult cells, known as induced pluripotent stem cells or iPS cells, were capable of differentiating into every type of tissue, the way embryonic stem cells do.
Earlier this week, the oil giant ExxonMobil announced a significant shift in direction: Rather than drilling ever downward in an attempt to find more oil, the company will invest heavily in green, growing things that can manufacture biofuel. Exxon plans to put $600 million into the production of algae-based biofuels, and will partner with the genetics company Synthetic Genomics run by genomics pioneer Craig Venter. The announcement came just a week after another industrial giant, Dow Chemical, declared its own investment in algae technology.
The biofuel industry is currently facing a shift from first-generation biofuels to so-called advanced biofuels as evidence mounts that corn-based ethanol and soybean biodiesel are not as ecologically, socially or economically sustainable as many first thought…. Algae have been touted as a better organic material for producing biofuel by many researchers and entrepreneurs. It does not take up any arable land and can be grown in controlled conditions; at a basic level algae only needs water, sunlight, carbon dioxide and some nutrients to grow [CNN].
It was only a few years ago that scientists figured out how to reprogram adult cells to make them act like multipurpose stem cells, but the next discoveries are coming fast and furious. Researchers had previously transformed human skin cells into so-called induced pluripotent stem (iPS) cells that can grow into any type of tissue; now, a new study reports that the same feat has been accomplished with pig cells. The achievement raises the possibility that genetically engineered pigs could be reared as organ donors, researchers say.
The created iPS cells could be genetically altered, and then cloned to produce pigs with certain traits. By adding or deleting certain genes, for example, researchers could produce pigs whose organs can be transplanted into patients without them being recognised and rejected. Efforts to do such xenotransplants have already been under way for at least a decade, but iPS cells are easier to genetically engineer and grow in the lab than pig embryos, opening up new possibilities for xenotransplantation [New Scientist]. Pigs are considered potential organ donors because their organs are already similar to those of humans in size and function.
Scientists have taken another step in cellular reprogramming that points the way towards the use of a patient’s own cells to treat genetic diseases. In a proof of concept study, researchers took skin cells from patients with a rare condition, Fanconi anemia, which causes skeletal problems and bone-marrow failure, and raises sufferers’ risk of cancer [Technology Review]. In the skin cells, the researchers fixed the genetic defects that caused the disease, and then reprogrammed the cells to act like stem cells capable of growing into any type of tissue.
The corrected stem cells could be grown into blood precursor cells for therapy. As these would carry a patient’s own DNA, except for the mutation responsible for the illness, they could be transplanted without risk of rejection by the body’s immune system [Times Online]. However, the patched up cells were not used to treat patients in this study, because it isn’t yet clear whether such cells are safe. Comments molecular geneticist Chris Mathew: “In future it may become possible to transfer the corrected stem cells back into the patient, but much work remains to be done before this can be transferred from the lab bench to the bedside” [The Scientist].
Researchers have endowed lab mice with the human version of a gene involved in language, and while the mice didn’t exactly sit up and start reciting poetry about cheese, they did show some intriguing differences in both their vocal patterns and brain structure.
Mice have their own form of the gene, called FOXP2, but they and all other animals lack key changes found only in humans and our evolutionary cousins, Neanderthals. Some researchers speculate that these differences may help explain why humans are the only animal able to communicate with complex languages, and not simple grunts, barks or songs [New Scientist]. By tweaking the gene in mice and changing it to the human form, researchers hoped to get a clue as to how our early hominid ancestors were changed by the new form of the gene.
Researchers have found a new way to reprogram human skin cells to act like multipurpose stem cells, and say their safe technique produces stem cells that are ready for medical use. If the researchers are right, clinical trials on the induced pluripotent stem (iPS) cells, which can turn into virtually any cell type and potentially be used to treat disorders ranging from spinal cord injury to diabetes, could start within two years [Nature News].
Many experts say that reprogrammed skin cells have several advantages over embryonic stem cells, for reasons both societal and medical. Using adult cells dodges the ethical controversy involved in taking cells from embryos, and it also raises the possibility that patients’ own cells could be used in their medical treatment, negating the chance that the cells would be rejected by their bodies. But reprogramming cells is still a scientific frontier, and researchers have struggled to find safe ways to accomplish the feat.
Five small monkeys that glow green under ultraviolet light are providing a beacon for medical research. Researchers introduced a jellyfish gene that codes for a fluorescent protein into the embryos of marmosets, and found that the resulting monkeys expressed the gene in all the cells of their body, including their egg and sperm cells–which means the genetically engineered primates can naturally pass on the foreign trait to their offspring. While creating a family of glowing monkeys doesn’t have obvious benefits for medical science, researchers say the study was really just a proof of concept.
Researchers have added genes to rhesus macaques before, but the new work with marmosets is the first to document that monkeys can pass an inserted gene along to future generations. That’s important because it opens the door to creating colonies of such “transgenic” monkeys by breeding, which would be far simpler than the cumbersome process of making each animal from scratch by inserting genes into embryos [AP]. Now that researchers have mastered the technique, they hope to create transgenic monkeys that carry genes associated with such diseases as Parkinson’s and Lou Gehrig’s disease.
All’s fair in the fight against the AIDS virus–including medical sneak attacks. Researchers have devised a novel strategy to attack HIV by completely bypassing the immune system and instead tricking the muscles into producing virus-fighting proteins.
The quest for an HIV vaccine has been given a bad prognosis recently, due to increasing agreement that the human immune system isn’t clever enough to outsmart the ever-changing surface of the virus [Technology Review]. But using the new technique, researchers were able to protect monkeys from infection by the simian immunodeficiency virus (SIV), the animal virus most closely related to HIV. While lead researcher Philip Johnson cautions that there’s no guarantee that the vaccination process will work in humans, he’s eagerly looking forward to human trials in a few years.
Most efforts at blocking AIDS have sought to stimulate the body’s immune system to produce antibodies that fight the disease. This model has worked for diseases such as measles and smallpox. It hasn’t done as well with HIV/AIDS; test vaccines have failed to produce a protective reaction. So Johnson decided to try something different. “We used a leapfrog strategy, bypassing the natural immune system response that was the target of all previous HIV and SIV vaccine candidates,” Johnson said [AP].
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].
For two squirrel monkeys nicknamed Dalton and Sam, life has gotten a lot more colorful. Researchers used gene therapy to correct the color blindness of the two adult monkeys, giving them the ability to distinguish between red and green for the first time. The fascinating accomplishment suggests that scientists may someday be able to cure other kinds of blindness in humans. And because the treated monkeys were “middle aged”, it challenges the assumption that gene therapies cannot work in adults because their brain connections are too set in their ways to change beneficially [New Scientist].
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?
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.
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 
Scientists have created 
Changes in an organism’s genome that once took years to make in a lab can now be done in a fraction of the time, thanks to a new method of 
From reprogrammed skin cells, scientists have made live mice.
Earlier this week, the oil giant ExxonMobil announced a significant shift in direction: Rather than drilling ever downward in an attempt to find more 
It was only a few years ago that scientists figured out how to reprogram adult cells to make them act like multipurpose 
Scientists have taken another step in cellular reprogramming that points the way towards the use of a patient’s own cells to treat 
Researchers have endowed lab mice with the human version of a gene involved in 
Researchers have found a new way to reprogram human skin cells to act like multipurpose 
Five small 
All’s fair in the fight against the 
