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nidthamsirisup

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

www.pbs.org/...junk-dna.html

noncoding DNA gene

shared by nidthamsirisup on 15 Apr 12 - No Cached
  • 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.
nidthamsirisup

Epigenetics: DNA Isn't Everything - 0 views

www.sciencedaily.com/...090412081315.htm

epigenetics genetics gene

shared by nidthamsirisup on 15 Apr 12 - Cached
  • 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.
Paige Prescott

DNA and Genetics - 2 views

What is the future of genetics research?

started by Paige Prescott on 25 Mar 12 no follow-up yet
orasa sukmark

Junk DNA Can Revive and Cause Disease, Study Finds - NYTimes.com - 0 views

www.nytimes.com/...20gene.html

shared by orasa sukmark on 30 Mar 12 - No Cached
  • can rise from the dead like zombies
  • dead gene come back to life and cause a disease
  • a dead gene come back to life and cause a disease.
  • ...16 more annotations...
  • Some of those genes, surprised geneticists reported Thursday, can rise from the dead like zombies, waking up to cause one of the most common forms of muscular dystrophy.
    • adisa narula
      adisa narula on 30 Mar 12
       
      Do these genes revive automatically?
  • It is a dominant genetic disease.
  • people who have the disease cannot smile.
  • FSHD affects about 1 in 20,000 people
  • function, if any, is largely unknown.
  • function, if any, is largely unknown
  • FSHD, is one of the most common forms of muscular dystrophy.
  • in a way FSHD was the easy case — it is a disease that affects every single person who inherits the genetic defect. Other diseases are more subtle, affecting some people more than others, causing a range of symptoms.
  • The dead gene was also repeated on chromosome 10, but that area of repeats seemed innocuous, unrelated to the disease. Only chromosome 4 was a problem.
  • chromosome 4 was a problem.
  • No one whose dead gene was repeated more than 10 times ever got FSHD
  • it was not completely inactive. It is always transcribed
  • copied by the cell as a first step to making a protein.
  • But the transcriptions were faulty, disintegrating right away. They were missing a crucial section, called a poly (A) sequence, needed to stabilize them.
  • But the transcriptions were faulty, disintegrating right away. They were missing a crucial section, called a poly (A) sequence, needed to stabilize them.
  • extra copies change the chromosome’s structure, shutting off the whole region so it cannot be used.
orasa sukmark

Making a Friendlier Mosquito - Biology Online - 1 views

www.biology-online.org/...aking_friendlier_mosquito.html

making mosquito biology Genes

shared by orasa sukmark on 16 Apr 12 - No Cached
  • Genetically modified mosquitoes that cannot transmit malaria are one hope for battling the disease that still kills over one million people a year. But that plan faces some serious snags, according to UC Davis researchers who are suggesting an alternative strategy.
  • nsmit malaria are one hope for battling the disease that still kills over one million people a year. But that plan face
  • Genetically modified mosquitoes that cannot transmit malaria are one hope for battling the disease that still kills over one million people a year.
  • ...7 more annotations...
  • enetically modified mosquitoes that cannot transmit malaria are one hope for battling the disease that still kills over one million people a year. But that plan faces some serious snags, according to UC Davis researchers who are suggesting an alternative strategy
  • releasing into the wild mosquitoes genetically engineered to resist malaria
  • If the resistant mosquitoes breed and spread their genes through the population, malaria transmission should be shut down.
  • the malaria resistance genes available are not very effective
  • , there's no way to reliably push the genes through the population.
  • Transposons are essentially DNA parasites that snip themselves in or out of the genome under the right circumstances. Scientists can add a new gene into a transposon and use it to carry that DNA into the insect genome. But it's in the interest of that transposon to just get rid of the extra DNA,
  • a transposon that gives an advantage to mosquitoes that already carry genes to block malaria, so that those genes spread through the population by natural selection.
  • orasa sukmark on 16 Apr 12
     
    scientists have found a way to reduce mosquitoes that can transmit malaria. 
chanon chiarnpattanodom

Cancer epigenetics takes center stage - 1 views

www.pnas.org/...392.full

shared by chanon chiarnpattanodom on 16 Apr 12 - No Cached
    • chanon chiarnpattanodom
      chanon chiarnpattanodom on 16 Apr 12
       
      DNA methylation is a chemical process where a methyl group is added on either the cytosine ring or the adenine ring, used in "higher leveled" organisms. Important in cell differentiation since methylation will cause cells to "remember" and remain differenciated instead of expressing other genes. 
  • Epigenetics is defined as modifications of the genome, heritable during cell division, that do not involve a change in the DNA sequence.
  • Epigenetic alterations in cancer include global hypomethylation
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  • the promoters of housekeeping genes that are generally protected from methylation.
  • may lead to aberrant silencing of tumor suppressor genes
  • discovered loss of imprinting (LOI) in cancer
  • Genomic imprinting, the subject of the report by Nakagawa et al. (2), is an epigenetic modification of a specific parental allele of a gene, or the chromosome on which it resides, in the gamete or zygote, leading to differential expression of the two alleles of the gene in somatic cells of the offspring.
  • we found that LOI can occur in the normal colonic mucosa of colorectal cancer patients with LOI in their tumors
  • This LOI was linked to cases showing microsatellite instability (MSI) in the tumors
  • However, these patients do not have mutations in mismatch repair genes
  • One potential cause of MSI in these sporadic cancers is hypermethylation and epigenetic silencing of the hMLH1 mismatch repair gene
  • Nakagawa et al. (2) now confirm the original study of Cui et al. that LOI occurs in both tumor and normal tissue of patients
  • The present study (2) also offers an intriguing mechanistic hypothesis to explain the relationship between H19 DMR methylation and LOI in these patients
  • Nevertheless, the study calls attention to this remarkable highly conserved multifunctional protein,
  • The potential link to CTCF suggested by this study also calls our attention to the link among DNA methylation, epigenetics, and chromatin.
  • A clue to the link between MSI and epigenetics may be provided by another sometimes overlooked common thread in epigenetics, namely DNA replication
  • repeat-induced gene silencing is thought to be propagated through hemimethylated intermediates during DNA replication
  • The studies of Cui et al. (11), Nishihara et al. (20), and Nakagawa et al. (2) suggest a new and provocative view of the timing of epigenetic changes in cancer.
  • Studies of transgenic mice with constitutive biallelic expression of IGF2, comparable to LOI, show reduced apoptosis and increased tumor formation
  • I conclude by noting that the distinction between cancer genetics and epigenetics has blurred considerably in recent years
  • Many conventional “genetic” mechanisms directly affect proteins that regulate chromatin,
Sasicha Manupipatpong

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

www.sciencedaily.com/...120415151347.htm

genes alzheimer's hippocampus shrinking

shared by Sasicha Manupipatpong on 16 Apr 12 - No Cached
  • 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
  • Sasicha Manupipatpong on 16 Apr 12
     
    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.
Changul Louis Yeum

Changes in Social Status Seen in Monkeys' Genes - 1 views

www.nytimes.com/...tus-seen-in-monkeys-genes.html

Genes gene

shared by Changul Louis Yeum on 12 Apr 12 - No Cached
  • Changul Louis Yeum on 12 Apr 12
     
    Social stress is known to have adverse health effects on both humans and primates. Now, researchers report that it also affects the immune system of female rhesus macaques at the genetic level.
chanon chiarnpattanodom

Genes an important factor in urinary incontinence - 1 views

www.sciencedaily.com/...110404142807.htm

Urinary Incontinence Genes

shared by chanon chiarnpattanodom on 11 Apr 12 - No Cached
  • chanon chiarnpattanodom on 11 Apr 12
     
    Scientists have studied how much is urinary incontinence controlled by genetics, rather than the environment by observing twins. 
Kaoko Miyazaki

lincRNA: A recently discovered RNA organizes stem cell differentiation - 0 views

scitechstory.com/...izes-stem-cell-differentiation

RNA lincRNA

shared by Kaoko Miyazaki on 11 Apr 12 - No Cached
  • Kaoko Miyazaki on 11 Apr 12
     
    Organizing how proteins assemble in embryonic cells and taking control over/deciding whether a stem cells stays pluripotent or not are only two of the main functions of the recently discovered lincRNAs. These new discoveries of lincRNAs and ongoing experiments only help researches such as Mitchell Guttman from the Broad Institute widen up the study of genetics and the human genome to a new field.
adisa narula

Breaking the Silence: The Rise of Epigenetic Therapy - 0 views

jnci.oxfordjournals.org/...874.full

cancer DNA genetics research epigenetic

shared by adisa narula on 12 Apr 12 - No Cached
  • adisa narula on 12 Apr 12
     
    Cancer epigenetics is hot. At the annual meeting of the American Association for Cancer Research in April, once-obscure principal investigators were feted by gaggles of admirers and many poster presenters mobbed by the curious. "It's one of the hottest areas of basic biology," said Paul Workman, Ph.D., director of cancer therapeutics at Cancer Research U.K.
wasin kusakabe

Athletic frogs have faster-changing genomes - 0 views

www.sciencedaily.com/...120412182332.htm

DNA Genomes Athletic Frogs

shared by wasin kusakabe on 14 Apr 12 - No Cached
    • wasin kusakabe
      wasin kusakabe on 14 Apr 12
       
      Physical activities can change the DNA sequence which can be passed on to later generations. However this has only been tested on frogs and may not apply to mammals like us.
  • Physically fit frogs have faster-changing genomes
  • Stretches of DNA accumulate changes over time
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  • athletic frogs tended to have faster-changing genomes.
  • During exercise, the circulatory system provides blood and oxygen to the tissues that are needed most
  • When physical activity has stopped, the rush of blood and oxygen when circulation is restored to those tissues produces a burst of free radicals that can cause wear and tear on DNA, eventually causing genetic changes that -- if they affect the DNA of cells that make eggs or sperm -- can be passed to future generations.
Nitchakan Chaiprukmalakan

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

scitechstory.com/...nsition-instant-shape-shifting

shared by Nitchakan Chaiprukmalakan on 13 Apr 12 - No Cached
  • 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
      Nitchakan Chaiprukmalakan on 13 Apr 12
       
      This is not accepted as a true fact yet and has to be proven.
Rafael Chen

Plant Geneticist Identifies Drought-Tolerant Gene - 2 views

www.sciencedaily.com/...981028144738.htm

shared by Rafael Chen on 16 Apr 12 - No Cached
  • isolation of the gene that controls drought tolerance in plants
  • enable a plant's leaves to stay green long after the last watering
  • plant hormone abscisic acid triggers the closure of the plant's stomata
  • ...3 more annotations...
  • controlled by the ERA1
  • By suppressing the gene -- and thereby keeping the stomata closed -- he found it is possible to control water loss so plants last longer
  • useful in applications such as the cut flower industry
  • Rafael Chen on 16 Apr 12
     
    Genetically engineering plants with a drought resistant gene may be beneficial in creating plants whom leaves would stay green long after the last watering.
Kantham Hongdusit

Niceness, Generosity May Have A Genetic Component - 0 views

www.medicalnewstoday.com/...244014.php

shared by Kantham Hongdusit on 15 Apr 12 - No Cached
  • Kantham Hongdusit on 15 Apr 12
     
    Psychologists from the Buffalo University and University of California have conducted a survey to find out if DNA can affect how a person perceives the world. They conclude that there is a specific gene, which has not yet been identified, that controls the receptors of oxytocin and vasopressin, hormones that display "niceness".
Rafael Chen

Scientists develop tools to make more complex biological machines from yeast - 0 views

www.sciencedaily.com/...120319194313.htm

shared by Rafael Chen on 15 Apr 12 - No Cached
  • creating a new type of biological "wire," using proteins that interact with DNA and behave like wires in electronic circuitry
  • it can be re-engineered over and over again
  • fundamental DNA components, called "promoters," which are needed for re-programming yeast
  • ...2 more annotations...
  • Future applications of this work could include tiny yeast-based machines that can be dropped into water supplies to detect contaminants, and yeast that records environmental conditions during the manufacture of biofuels to determine if improvements can be made to the production process.
  • help to improve things such as pollution monitoring and cleaner fuels
  • Rafael Chen on 15 Apr 12
     
    Scientist uses yeast as the foundations in making more complex biological machines through genetic engineering.
Sea Maskulrath

Why having sex really IS the best thing to do: Gene mapping finally proves mating is be... - 0 views

www.dailymail.co.uk/...-evolve-self-reproduction.html

mapping gene DNA genetics

shared by Sea Maskulrath on 15 Apr 12 - No Cached
  • Why having sex really IS the best thing to do
  • is better for evolution than self-reproduction
  • Having sex allows us to evolve more effectively than species which reproduce without a partner, according to tests that claim to finally prove the long-held theory.
  • ...6 more annotations...
  • cording to the study by the University of Edinburgh.
  • Combining the genes of two parents – rather than one in the case of fruit flies, stick insects and other animals – allows for damaging DNA to be removed within a few generations.
  • Meanwhile, creatures who reproduce asexually are more likely to be lumbered with disease-causing genes
  • h longer, a
  • or muc
  • This is because individuals who inherit healthy genes tend to flourish and pass on their DNA to the next generatio
  • Sea Maskulrath on 15 Apr 12
     
    well, I guess SEX is the best way to develop a super human for the future + I know everyone gonna love it :) 
Sea Maskulrath

The Ice Age Elephant - Mammuthus primigenius | Scitech | The Earth Times - 0 views

www.earthtimes.org/...1914

ice elephant times DNA genetics

shared by Sea Maskulrath on 15 Apr 12 - No Cached
  • preserved remains of a shaggy monster that lived in Siberia at -40°C 10,000 years ago have been uncovered;
  • The frozen and p
  • Only microscopic amounts of DNA are left on the skeletons, including all the bacteria that lived on the animals. No usable DNA is therefore often found in bone, but mammoth hair is plentiful. Shampooed and bleached and digested, the hair, even at 18,000 years old, can have 90% of the DNA left. The genome shows 4 different "races" of this species. Research has also shown the recreated blood of mammoth. It doesn't decrease its oxygen capacity at the low temperatures the mammoth had to endure. That increased oxygen-offloading ability was one of the essential physiological changes evolved especially for this species, just like the Yuka kidney.
  • ...2 more annotations...
  • reserved remains of a shaggy monster that lived in Siberia at -40°C 10,000 years ago have been uncovered;
  • Cloning the mammoth has been an aim of Japanese scientists for several years. They discovered almost intact bone marrow from a thigh bone in Yakutsk and hope to use a female elephant for what is obviously more than a simple experiment within the next 5 years.
  • Sea Maskulrath on 15 Apr 12
     
    The return of the giant, not a long wait :) 
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