Thursday, December 15, 2011
A new study, led by researchers with the Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute, has identified a gene mutation that they estimate dates back to 11,600 B.C., making it the second oldest human disease mutation yet discovered. They estimate that the mutation arose in the Middle East some 13,600 years ago, and is described in people of Arabic, Turkish and Jewish ancestry. It causes a rare, inherited vitamin B12 deficiency called Imerslund-Gräsbeck Syndrome (IGS).
It originated in a single, prehistoric individual and was passed down to that individual’s descendants. This is unusual because such “founder mutations” usually are restricted to specific ethnic groups or relatively isolated populations.
Because the mutation was found in such diverse populations, the researchers were unsure whether it was a true founder mutation that first arose in one individual and was passed down, or whether it was simply a mutation that recurred frequently over time in different populations. Analysis of the gene sequences on either side of the mutation (the haplotype in both the Muslim and Jewish families), pointed to a single mutational event rather than repeated events.
Principal investigator Stephan M. Tanner says, “Our findings permit reliable genetic diagnostics in suspected cases of IGS in that this mutation should be considered first when genetically screening patients from these populations.” This mutation accounts for more than half of the cases in the aforementioned populations and for about 15 percent of cases worldwide.
Four gene variants, all members of the glutamate receptor gene family, appear to be involved in vital brain signaling pathways in a group of children with attention deficit hyperactivity disorder (ADHD). The genes involved affect neurotransmitter systems in the brain that have been implicated in ADHD, and now there is a genetic explanation for this link that applies to this subset of children.
ADHD is fairly common and tends to run in families. Though it is considered by many to be the most commonly over-diagnosed disorder, it is thought to affect about 7% of kids of school age and a smaller percentage of adults.
Researchers from the Center for Applied Genomics at The Children's Hospital of Philadelphia conducted whole-genome analyses of 1,000 kids with ADHD compared with 4,100 others of the same age who did not have ADHD. They looked for duplications or deletions of DNA sequences (copy number variations, or CNVs), and then compared the preliminary findings with various cohorts, made up of 2,500 kids with and 9,200 without ADHD. They identified They identified four genes with a considerably greater number of CNVs in the ADHD children. They were all glutamate receptor (GMR) genes. The one with the strongest result was gene GMR5. Members of the GMR gene gamily, aong with genes they interact with, affect nerve transmission, the formation of neurons, and interconnections in the brain. Glutamate is an amino acid and neurotransmitter. The fact that children with ADHD are more likely to have alterations in these genes reinforces previous evidence that the GRM pathway is important in ADHD.
Co-first author Josephine Elia, M.D., says, "This research will allow new therapies to be developed that are tailored to treating underlying causes of ADHD. This is another step toward individualizing treatment to a child's genetic profile."
Wednesday, December 14, 2011
Tuesday, December 13, 2011
Anthropologists have recently revised their view of how early human societies were structured. This shift ultimately brings new insights into the evolution of humans from apes. This new belief is concerned with how early human groups would have been more cooperative and willing to learn from one another than the chimpanzees from which our ancestors split.
Anthropologists have assumed until now that hunter-gatherer bands consist of people fairly closely related to one another, much as chimpanzee groups do, and that kinship is a main motive for cooperation within the group. Natural selection, which usually promotes only selfish behavior, can reward this kind of cooperative behavior, called kin selection, because relatives contain many of the same genes.
A team of anthropologists led by Kim R. Hill of Arizona State University and Robert S. Walker analyzed data from 32 living hunter-gatherer peoples and found that the members of a band are not highly related. Fewer than 10 percent of people in a typical band are close relatives, meaning parents, children or siblings, they report in Friday’s issue of Science.
The finding corresponds to an influential new view of early human origins proposed by Bernard Chapais, a primatologist at the University of Montreal. Dr. Chapais showed how a simple development, the emergence of a pair bond between male and female, would have allowed people to recognize their relatives, something chimps can do only to a limited extent. When family members dispersed to other bands, they would be recognized and neighboring bands would cooperate instead of fighting to the death as chimp groups do.
Paleoanthropologists have recently discovered an apelike creature with human features, whose fossil bones were discovered in a South African cave. Les Berger of the University of Witwatersrand in Johannesburg, the founder of the fossils, believes that the new species is the most plausible known ancestor of archaic and modern humans. He also believes that if accepted, this finding would radically redraw the present version of the human family tree, placing the new fossils in the center. The new species, in his view, should dislodge Homo habilis, the famous tool-making fossil found by Louis and Mary Leakey, as the most likely bridge between the australopithecenes and the human lineage. In this particular case, there are many uncertainties regarding the fossil record from that time, including when the human lineage first emerged and how Homo habilis fits in the picture. The principal significance of the new fossils is not that Australopithecus sediba is necessarily the direct ancestor of the human genus, other scientists said, but rather that the fossils emphasize the richness of evolutionary experimentation within the australopithecine group.
In tests conducted at the Oxford Radiocarbon Accelerator Unit in England, the baby teeth from Italy were dated at 43,000 to 45,000 years old. And in the absence of early fossils, archaeologists had not been sure who made some of the stone tools they were uncovering, the arriving humans or the Neanderthals. It had been generally assumed that modern humans probably entered Europe at least as early as 45,000 years ago, based on changing patterns of artifacts that soon followed. Anyhow, this new discovery will help researchers evaluate some of the evolutionary events in which society has been interested in for decades.
By Alwin Firmansyah
Monday, December 12, 2011
The collaboration took place among the Salk Institute of Biological Studies and two Swiss institutes, the Ecole Polytechnique Federale de Lausanne, and the University of Lausanne.
The study suggests that here is a tiny inhibitor that could be responsible for determining the strength of our muscles. This conclusion and procedure makes the work being done somewhat unique, because most studies in this area focus on promoting genetic accelerators instead of focusing on inhibiting genetic inhibitors. NCoR1, a gene regulator usually inhibits muscle growth. So when NCoR1 is suppressed, the body is able to send more energy to muscle cells and enhance cellular activity in the muscles. The scientists genetically removed the NCoR1 from fat and muscle cells in mice and in certain types of worms. In the absence of NCoR1, muscle tissue developed much more effectively, and were ultimately more massive and had more cellular mitochondria than the muscles of the mice where NCoR1 was still at work. The mice’s endurance and cold tolerance also dramatically improved.
This discovery enables scientists to give the benefits of exercise to sedentary mice by manipulating NCoR1. Currently, just manipulation is purely genetic, but this work could lead to developing drugs molecules or therapeutic solutions for humans who are unable to exercise due to health complications like obesity, diabetes, frailty (due to old age) or immobility (due to accidents). "This could be used to combat muscle weakness in the elderly, which leads to falls and contributes to hospitalizations," Auwerx, one of the scientists working on the study, says. "In addition, we think that this could be used as a basis for developing a treatment for genetic muscular dystrophy." When human trials begin and drug development begins in earnest, there is no question that the athletic community, as well as the medical one, will be greatly interested by the findings.
Sources: Salk Institute (2011, November 21). Tweaking a gene makes muscles twice as strong: New avenue for treating muscle degeneration in people who can't exercise. ScienceDaily. Retrieved December 1, 2011, from http://www.sciencedaily.com /releases/2011/11/111121104509.htm; The Study: http://www.cell.com/abstract/S0092-8674%2811%2901223-2
Waiting for Sequences: Morris Goodman, Immunodiﬀusion
Experiments, and the Origins of Molecular Anthropology
Molecular Anthropology Meets Genetic Medicine to Treat Blindness in the North African Jewish Population: Human Gene Therapy Initiated in Israel
A Population Genomic Analysis of the Peopling of the New World
Goodman's work began in the 1960s and continued until his death in 2010. Throughout his extensive career, he published hundreds of articles and received a number of awards - including the Charles Darwin lifetime achievement award - and other honors for his contributions to the field of molecular anthropology.
Morris Goodman (1925–2010): Founder of the Field of Molecular Anthropology
Saturday, December 10, 2011
When a doctor suspects that a patient is suffering from blood poisoning, they must draw a blood sample and then send it to a central laboratory for testing. Unfortunately this takes up time and this time could cost the patient his or her life. With the recent development of a biochip though, this will not be a problem in the future. The biochip, which makes it possible to analyze blood right there in the hospital and have results within twenty minutes, was developed by scientists at the Fraunhofer Institute for Physical Measurement Techniques IPM in Freiburg.
The biochip requires a "fully automatic deceive to carry out all the examination steps". In the device red blood cells are separated from the blood and the plasma that remains is guided onto the biochip. Our immune systems produce certain proteins when we suffer from sepsis and there are antibodies on the chip that fit these proteins, so that if these proteins are are in fact present in the blood, the antibodies fish them out and bind them to the chip. A solution containing the appropriate antibodies, which have been marked with a fluorescent dye, is then used to rune the chip. If the patient has blood poisoning the chip lights up and if the patient is healthy the chip stays dark. In the future this biochip will be used to test for different proteins at the same time in one cycle.
"More than 100,000 in North America die every year due to hospital acquired infections at a cost of $30 billion. That's 100,000 people every year who are dying from largely preventable infections." Shocking? I know I was extremely shocked to read this. That is why it was slightly relieving to read in this article that recently a Queen's University infectious disease expert, Dr. Dick Zoutman, in collaboration with Dr. Michael Shannon of Medizone International has developed a disinfection system that may hospital rooms all over the world. Not only that, but it may also be used in food preparation areas and processing plats after outbreaks as well as to stop bed bug outbreaks in hotels and apartments.
The system involves pumping Medizone-specific ozone and hydrogen peroxide vapor gas mixture into the targeted room to completely sterilize everything. It is more effective in killing bacteria than wiping down the room and it is also faster than other methods. The technique imitates the antibodies that Mother Nature uses to kill bacteria in humans. As quoted by Dr. Zoutman, "this is the future."
Researchers at Rensselaer Polytechnic Institute have developed a new method to design antibodies aimed at combating disease. Designing antibodies is rather difficult because it requires a very specific combination of antibody loops in order to bind to and neutralize each target. Therefore the arrangement and sequence of the antibody loops is extremely important. Scientists have been unable to realize this as a method for designing antibodies to combat specific ailments thus far due to the incredible complexity of the designing process, but just recently the process was used to create antibodies that target the Alzheimer's protein.
The Alzheimer's protein, the specific protein that causes Alzheimer's disease, sticks to other Alzheimer's proteins to create protein particles, which then damage the normal, healthy functions of the brain. The research led by Assistant Professor of Chemical and Biological Engineering Peter Tessier uses the same molecular interactions that cause these harmful proteins to stick together and form the toxic particles that are a "hallmark of the disease". The good thing is that these new Alzheimer's antibodies only latch on to the damaging clumped proteins and not the unassociated harmless monomers or single peptides. Scientists will need to learns more about this method, but for the future, the researchers see this technique being used to target similar types of protein particles in disorders such as Parkinson's disease and mad cow disease.