Skip to main content

Home/ RIS IB Biology/ Group items tagged much

Rss Feed Group items tagged

Mickey Tsai

Niceness a combination of genetics and environment, the Neurogenics of Niceness study f... - 0 views

  • BEING a nice person could come down to having a good set of genes
  • "kind" behaviour of more than 700 individuals was partly linked to receptor genes for oxytocin and vasopressin.
  • uch of the hormone you have, it's how responsive your brain is to the hormo
  • ...2 more annotations...
  • It's not about how much of the hormone you have, it's how responsive your brain is to the hormones
  • "(Niceness) is a combination of genetics and your environment."
  •  
    A study shows that genetics could play a role in determining "niceness". The kind behavior is found to be linked to receptor genes for oxytopic and vasopressin. People that are more responsive to it are more inclined to donate money, pay taxes, give blood, report crime etc. It isn't about how much of the hormone you have but how responsive you are to it. Of course genetics isnt the only factor, if you are surrounded by nice people it is likely that it would rub off on you.
Pop karnchanapimonkul

Sight Seen: Gene Therapy Restores Vision in Both Eyes: Scientific American - 0 views

  • gene therapy to treat blindness in 12 adults and children with Leber's congenital amaurosis (LCA), a rare inherited eye disease that destroys vision by killing photoreceptors—light-sensitive cells in the retina at the back of the eye.
  • genetic mutations in retinal cells. One mutated gene that causes the disorder is named RPE65. An enzyme encoded by RPE65 helps break down a derivative of vitamin A called retinol into a substance that photoreceptors need to detect light and send signals to the brain.
  • injected a harmless virus carrying normal copies of RPE65
  • ...8 more annotations...
  • subsequently began producing the enzyme
  • proved so much they no longer met the criteria for legal blindness
  • injected the functional genes into the previously untreated eye
  • improved as soon as two weeks after the operation: They could navigate an obstacle course, even in dim light, avoiding objects that had tripped them up before, as well as recognize people's faces and read large signs
  • brains were much more responsive to optical input as well.
  • second round of gene therapy further strengthened the brain's response to the initially treated eye as well as the newly treated one
  • that neuroplasticity plays a role
  • visual cortex responding to the newly flowing channel of information from the second eye bolster activity in areas of the visual cortex responding to the initially treated eye.
  •  
    Article about how the enzyme produced from gene therapy is used to cure blindness in an eye genetic disease.
chanon chiarnpattanodom

Genes an Important Factor in Urinary Incontinence - 1 views

  •  
    Scientists have studied how much is urinary incontinence controlled by genetics, rather than the environment by observing twins. 
Mickey Tsai

Autism gender bias clue found - Health - CBC News - 0 views

  • four times more common among males than females.
  • rare family with four generations in which males carrying the glitch were affected but females were not.
  • When male fetuses are missing one copy of the gene, it throws off their developmental process enough to lead to autism but female biology differs enough that it doesn't matter.
  • ...2 more annotations...
  • now that doctors know that the SHANK 1 gene is involved and it can be tested for, they'll know to follow affected males very closely and offer treatments early on.
  • lved and it can be tested for, they'll know to follow affected males very c
  •  
    Scientists have long wondered why autism is much more common among males than females. When males miss one copy of a gene it messes up the development process enough to cause autism but female biology differs enough to make it not matter. Now that scientists have identified that the SHANK 1 gene is involved they can test for it and could offer treatments early.
Pop karnchanapimonkul

Dieting During Pregnancy Increases Risk Of Obesity And Diabetes For Offspring - 0 views

  • babies of mothers who diet around the time of conception and in early pregnancy, may have an increased risk of obesity and type 2 diabetes throughout their lives. This study provides exciting insights into how behavior can lead to epigenetic changes in offspring related to obesity and disease.
  • dieting around the time a baby is conceived may increase the chance of the child becoming obese later in life
  • changes in the genes that control food intake and glucose levels that may lead to obesity and diabetes.
  • ...1 more annotation...
  • epigenetic changes with alterations in the structure of the DNA and its associated proteins, histones, which affects the way that genes can behave in later life.
  •  
    Article about how dieting during pregnancy cause offsprings to have a change in genes.
nidthamsirisup

Mysterious Noncoding DNA: 'Junk' or Genetic Power Player? | PBS NewsHour - 0 views

  • Genes represent only a tiny fraction -- 1 percent -- of our overall genetic material. Then there's the other 99 percent of our DNA -- the stuff that doesn't make protein
  • Researchers have found that some of this noncoding DNA is in fact essential to how our genes function and plays a role in how we look, how we act and the diseases that afflict us.
  • Embedded in this 99 percent is DNA responsible for the mechanics of gene behavior: regulatory DNA. Greg Wray of Duke University's Institute for Genome Sciences and Policy describes the regulatory DNA as the software for our genes, a set of instructions that tells the genome how to use the traditional coding genes.
  • ...5 more annotations...
  • "It's like a recipe book," Wray said. "It tells you how to make the meal. You need to know the amounts. You need to know the order. The noncoding DNA tells you how much to make, when to make it and under what circumstances."
  • common diseases are probably more influenced by regulatory differences, Harismendy said. These include Type 2 diabetes, Crohn's disease, Alzheimer's Disease and a variety of cancers, including breast, colon, ovarian, prostate and lung.
  • According to Wray, research has shown that diseases like bipolar syndrome and clinical depression may be associated with noncoding mutations that determine whether the brain is producing too much or not enough of a particular neurotransmitter. One noncoding mutation gives a person almost complete protection against the nasty malaria parasite, plasmodium vivax.
  • Another piece of noncoding DNA regulates the enzyme responsible for lactose tolerance, the ability to digest milk. Research by Wray and other scientists has shown that in four populations where dairy consumption is a vital part of the diet, new mutations have appeared that essentially keep the gene that produces the lactase enzyme from switching off.
  • And recent research done by evolutionary biologists suggests that differences in regulatory DNA may represent a major part of what separates us from chimpanzees.
orasa sukmark

Shot of Young Stem Cells Makes Rapidly Aging Mice Live Much Longer and Healthier - Gate... - 1 views

  • animals that got the stem/progenitor cells improved their health and lived two to three times longer than expected,
  • "Our experiments showed that mice that have progeria, a disorder of premature aging, were healthier and lived longer after an injection of stem cells from young, healthy animals," Dr. Niedernhofer said. "That tells us that stem cell dysfunction is a cause of the changes we see with aging."
  • "Typically the progeria mice die at around 21 to 28 days of age, but the treated animals lived far longer -- some even lived beyond 66 days. They also were in better general health."
  • ...2 more annotations...
  • we injected stem/progenitor cells from young, healthy mice into the abdomens of 17-day-old progeria mice,
  • As the progeria mice age, they lose muscle mass in their hind limbs, hunch over, tremble, and move slowly and awkwardly. Affected mice that got a shot of stem cells just before showing the first signs of aging were more like normal mice, and they grew almost as large.
  •  
    the experiment from the University of Pittsburgh shows that the mice can be stronger live longer after they were injected with stem cells from young healthy animals.
Sasicha Manupipatpong

Gene switches do more than flip 'on' or 'off': Can exhibit much more complex binding be... - 1 views

  • right genes for the job are turned on only in the specific cells where they are needed
  • molecular "clutch" that converts treadmilling to a stable bound state, moving the transcription process forward to completion to turn the gene on
  • act like a switch; they are either "on" (bound to DNA) or "off" (not bound)
  • ...12 more annotations...
  • can exhibit much more complex binding behavior
  • transcription factors' binding process is dynamic and involves more than just being bound or unbound
  • In addition to a stable binding state (on or off)
  • "treadmilling," where no forward transcription process is occurring
  • indicator of whether a gene was turned on or off
  • measure and calculate how long a protein is associated with all of the different genes it regulates
  • proteins that bind in the stable state are associated with high levels of gene transcription
  • if we can regulate the transition between treadmilling and stable binding, we can regulate the outcome in terms of gene expression
  • genetic medicine -- a new way to regulate the 'switches' that turn gene expression associated with disease on or off.
  • measured how long it took the competitor transcription factor to replace the resident protein and used this data to calculate the residence time at each location in the genome
  • specific proteins called "transcription factors" that control which genes are turned on or off in cells by binding to nearby DNA
  • new insights on how cells respond to developmental cues and how they adapt to changing environmental conditions
  •  
    Genes have been discovered to be more complex than we previously thought--rather than having only on and off states, there is an intermediate state called "treadmilling".
Pop karnchanapimonkul

The Ballooning Brain: Defective Genes May Explain Uncontrolled Brain Growth in Autism: ... - 0 views

  • linked atypical gene activity to excessive growth in the autistic brain
  • autistic brain sprouts an excess of neurons and continues to balloon during the first five years of life, as all those extra neurons grow larger and form connections.
  • start to lose neural connections, faster than typical brains
  • ...11 more annotations...
  • 67 percent more neurons in their prefrontal cortex (PFC) than typical children
  • executive functions"—high-level thinking, such as planning ahead, inhibiting impulses and directing attention.
  • In brain tissue from both autistic children and autistic adults, genes coding for proteins that identify and repair mistakes in DNA were expressed at unusually low levels. Additionally, all autistic brains demonstrated unusual activity levels for genes that determine when neurons grow and die and how newborn neurons migrate during early development
  • Some genes involved in immune responses, cell-to-cell communication and tissue repair, however, were expressed at unusual levels in adult autistic brains, but not in autistic children's brains
  • autistic child develops in the womb, something—an inherited mutation or an environmental factor like a virus, toxin or hormone—muffles the expression of genes coding for proteins that usually fix mistakes in sequences of DNA
  • Errors accumulate.
  • The genetic systems controlling the growth of new neurons go haywire, and brain cells divide much more frequently than usual, accounting for the excess neurons found in the PFC of autistic children.
  • autistic brain grow physically larger and form more connections than in a typical child's brain.
  • immune system reacts against the brain's overzealous growth,
  • Not all researchers, however, accept
  • If scientists definitively link autism to a characteristic sequence of changes in gene expression and unusual neural growth, then it becomes possible to target and reverse any one of the thousands of steps in that sequence.
  •  
    Article about how genetic expression may be the cause for autism.
chanon chiarnpattanodom

Genes an important factor in urinary incontinence - 1 views

  •  
    Scientists have studied how much is urinary incontinence controlled by genetics, rather than the environment by observing twins. 
Nitchakan Chaiprukmalakan

Proteins and quantum transition: Instant shape-shifting - 0 views

  • The genetic code in DNA provides the template to manufacture protein into all the cells of an organism.
  • Proteins are made by stringing together amino acids. For general purposes there are twenty amino acids in protein and they can be put together in endless combinations, some in short chains (yeast averages 466 amino acids), some long chains (titins have nearly 27,000 amino acids) and everything in-between. The pattern of amino acids determines much of the functionality of the protein.
  • Proteins are three-dimensional puzzle pieces. They are generally very complicated in shape. Even a small protein of only 100 amino acids can theoretically have 10^100 (ten to the hundredth power) different configurations.
  • ...7 more annotations...
  • most protein reconfigurations occur in nanoseconds
  • In research on proteins, it was assumed (given their chemical composition) proteins would uniformly fold as they cool down and unfold as they heat up. (Think of a balloon expanding and shrinking with the temperature of the air inside.) The experiments didn’t bear this out; the rate of folding or unfolding according to temperature change was unequal (asymmetric) and uneven (nonlinear).
  • In recent biochemistry a great deal of work is done with ‘tagging’ or ‘marking’ molecules with fluorescent and phosphorescent materials. It’s well known that fluorescence and phosphorescence are phenomena closely related to protein folding and they can only be understood in terms of quantum transition between molecules.
  • With a quantum transition, the protein could change configuration by ‘jumping’ – skipping all the transition steps – to the final configuration. They call this quantum folding and they developed a mathematical model that shows how the folding, which is virtually instantaneous, would react to change in temperature.
  • Their quantum transition model matched the folding curves for 15 different proteins and also provides an explanation for the different rates of folding and unfolding among these proteins.
  • Luo and Lu’s paper is short, a mere 16 pdf pages, and the model is unpretentious mathematically. (Luo has several other related papers on arXiv.) It comes from unknown researchers in an unknown corner of the academic world, and it’s published on the open-source arXiv system. The lack of pedigree means that it will take more time than usual for scientists around the world to learn of it, examine it, and possibly test it.
    • Nitchakan Chaiprukmalakan
       
      This is not accepted as a true fact yet and has to be proven.
nidthamsirisup

Engineered stem cells seek out and kill HIV in living mice - 0 views

  • human stem cells can be genetically engineered into HIV-fighting cells
  • surrogate model
  • CD8 cytotoxic T lymphocytes -- the "killer" T cells that help fight infection -- from an HIV-infected individual and identified the molecule known as the T cell receptor, which guides the T cell in recognizing and killing HIV-infected cells.
  • ...12 more annotations...
  • cloned the receptor and used this to genetically engineer human blood stem cells.
  • mature T cells that can attack HIV in tissues where the virus resides and replicates.
  • CD4 cells are white blood cells that are an important component of the immune system, helping to fight off infections.
  • CD4 "helper" T cells
  • engineering stem cells to form immune cells that target HIV is effective in suppressing the virus in living tissues in an animal model
  • increased
  • HIV in the blood decreased.
    • wasin kusakabe
       
      Using mice as lab rats, researchers are able to produce a large amount of T cells that can fight off HIV more effectively.
  • The engineered stem cells developed into a large population of mature, multi-functional HIV-specific CD8 cells that could specifically target cells containing HIV proteins. The researchers also discovered that HIV-specific T cell receptors have to be matched to an individual in much the same way an organ is matched to a transplant patient.
  • Expanding on previous research providing proof-of-principle that human stem cells can be genetically engineered into HIV-fighting cells
  • In this current study, the researchers similarly engineered human blood stem cells and found that they can form mature T cells that can attack HIV in tissues where the virus resides and replicates. They did so by using a surrogate model, the humanized mouse, in which HIV infection closely resembles the disease and its progression in humans.
  • increased, while levels of HIV in the blood decreased. CD4 cells are white blood cells that are an important component of the immune system, helping to fight off infections. These results indicated that the engineered cells were capable of developing and migrating to the organs to fight infection there.
  •  
    Stem cells that are engineered to produce T cells that can help fight off HIV.
nidthamsirisup

Epigenetics: DNA Isn't Everything - 0 views

  • Research into epigenetics has shown that environmental factors affect characteristics of organisms. These changes are sometimes passed on to the offspring.
  • A certain laboratory strain of the fruit fly Drosophila melanogaster has white eyes. If the surrounding temperature of the embryos, which are normally nurtured at 25 degrees Celsius, is briefly raised to 37 degrees Celsius, the flies later hatch with red eyes.
  • crossed the flies for six generations. In this experiment, they were able to prove that the temperature treatment changes the eye colour of this specific strain of fly, and that the treated individual flies pass on the change to their offspring over several generations. However, the DNA sequence for the gene responsible for eye colour was proven to remain the same for white-eyed parents and red-eyed offspring.
  • ...7 more annotations...
  • Epigenetics examines the inheritance of characteristics that are not set out in the DNA sequence.
  • important factors are the histones, a kind of packaging material for the DNA, in order to store DNA in an ordered and space-saving way. It is now clear that these proteins have additional roles to play. Depending on the chemical group they carry, if they are acetylated or methylated, they permanently activate or deactivate genes.
  • New methods now allow researchers to sometimes directly show which genes have been activated or deactivated by the histones
  • The genetic information of the DNA is passed on along with the relevant epigenetic information for the respective cell type.
  • A similar question remains for the inheritance of the epigenetic characteristics from parents to offspring. They now know that when the gametes are formed, certain epigenetic markers remain and are passed on to the offspring. The questions, which are currently being researched, are how much and which part of the epigenetic information is preserved and subsequently inherited.
  • Diet and epigenetics appear to be closely linked. The most well known example is that of the Agouti mice: they are yellow, fat and are prone to diabetes and cancer. If Agouti females are fed with a cocktail of vitamin B12, folic acid and cholin, directly prior to and during pregnancy, they give birth to mainly brown, slim and healthy offspring. They in turn mainly have offspring similar to themselves.
  • Environmental factors, which change the characteristics of an individual and are then passed on to its offspring, do not really fit into Darwin’s theory of evolution. According to his theory, evolution is the result of the population and not the single individual. “Passing on the gained characteristics fits more to Lamarck’s theory of evolution”, says Paro.
pet-chompoo sa-ngarmangkang

Craving Coffee? It Might Be in Your Genes - Slashfood - 0 views

  • 3 o'clock caffeine craving can also be traced back to your gene
  • depending on whether you carry a "high-consumption" variant or "low-consumption" variant of either gene determines just how fast or slow you metabolize caffeine
  • genetics plays a big role in a lot of behaviors, such as smoking and alcohol consumption
  • ...2 more annotations...
  • how much caffeine we drink."
  • CYP1A2 and AHR,
pet-chompoo sa-ngarmangkang

BBC News - 'Tipsy' alcohol gene 'could help curb alcoholism' - 0 views

  • people who react strongly to alcohol are less likely to become addicted
  • the gene we have found tells us a lot about how alcohol affects the brain
  • Most of the alcohol people consume is broken down in the liver, but some is metabolised in the brain by an enzyme which the CYP2E1 gene
  • ...2 more annotations...
  • "tipsy" version of CYP2E1 break down alcohol more readily, which explains why they feel the effects of alcohol much quicker than others
  • CYP2E1 on chromosome 10 appears to dictate whether a person can hold their drink better than others.
Sasicha Manupipatpong

Memory in adults impacted by versions of four genes - 2 views

  • advanced understanding of the genetic components of Alzheimer's disease and of brain development.
  • understanding of the genetic components of Alzheimer's disease and of brain development
  • certain versions of four genes may speed shrinkage of a brain region involved in making new memories
  • ...12 more annotations...
  • hippocampus, normally shrinks with age, but if the process speeds up, it could increase vulnerability to Alzheimer's disease
  • two genes associated with intracranial volume -- the space within the skull occupied by the brain when the brain is fully developed in a person's lifespan
  • gene variants identified in the first study do not cause Alzheimer's, but they may rob the hippocampus of a kind of "reserve" against the disease
  • cause cell destruction and dramatic shrinkage of this key brain site
  • almost twice the Alzheimer's risk if he or she had these versions of the gene
  • if a person with one of these variants did get Alzheimer's, the disease would attack an already compromised hippocampus and so would lead to a more severe condition at a younger age than otherwise
  • Alzheimer's disease causes much of its damage by shrinking hippocampus volume
  • loses a greater-than-average amount of volume due to the gene variants we've identified, the hippocampus is more vulnerable to Alzheimer's
  • associations impacting intracranial volume, which is an indirect measure of the size of the brain at full development.
  • brain volume and intracranial volume are both highly heritable
  • no associations for brain volume
  • one of these genes has played a unique evolutionary role in human development, and perhaps we as a species are selecting this gene as a way of providing further advances in brain development
  •  
    The shrinking of the hippocampus, which occurs with age in normal people, was found to be accelerated by certain versions of four genes, which could increase susceptibility to Alzheimer's disease, which also affects the volume of the hippocampus.
1 - 16 of 16
Showing 20 items per page