BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: genetics (Page 2 of 4)

CRISPR/Cas9: Controlling Genetic Inheritance in Mammals

Often the subject of debate, CRISPR/Cas 9 has come to the forefront of the scientific community as its development bridges the worlds of Sci-Fi and reality. Yet while CRISPR/Cas9 has been successfully used in altering the genetic inheritance of insects, applying the same technology to mammals has proven to be significantly more complex. With the recent development of active genetics technology in mice by UC San Diego researchers, a huge stride has been made for the much contested future of gene technology.

Releasing their findings in January, the team led by Assistant Professor Kimberly Cooper engineered a copycat DNA element into the Tyrosinase gene controlling fur color. The copycat DNA results in mice that would have been black appearing white. Over two years they determined the copycat element could be copied from one chromosome to another, repairing breaks targeted by CRISPR.  Ultimately, the genotype was converted from heterozygous to homozygous.

Following the success of her lab’s single gene experiment, Cooper hopes to use the technology to control the inheritance of multiple genes and traits in mice. Her experiment, the first active genetic success in mammals, has biologists hopeful for  future development of gene drive technologies to balance biodiversity and mitigate the adverse effect of invasive species.

Strong Genes Equal Strong Immune System

Although scientists have long agreed that antibodies are in integral part of building up the body’s immune system, there is new evidence that strongly suggests genetic factors play a large role in determining how well the immune system builds and uses these antibodies when fighting disease.

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In a recent study, “researchers from James Cook University’s Australian Institute of Tropical Health and Medicine (AITHM) and the University of Queensland’s (UQ) Diamantina Institute have analyzed blood samples from 1835 twins and thousands of their siblings.” The team looked at the body’s immune response to “six common human viruses, including the Human Herpes virus, Parvovirus, Epstein Barr virus and the Coxsackie virus.” The team determined that genes passed down by parents are the major factor in how powerfully an immune system responds to diseases. “These genes determine whether you mount an intense or weak immune response when confronted with a viral infection,” says Associate Professor Miles.

“Demonstrating that antibody response is heritable is the first step in the eventual identification of individual genes that affect antibody response.” The researchers’ next goal is to identify the superior genes in order to, “imitate ‘super defenders’,” and “design next generation vaccines.”

 

Click Here to Learn About the Tomato’s Fancy New Makeover

The sun rose on a dimly light Monday morning when Adriano Nunes-Nesi, Lázaro E.P. Peres, Agustin Zsögön, Lucas de Ávila Silva, Ronan Sulpice, and Emmanuel Rezende Naves published their groundbreaking discovery that could revolutionize the cultivation of chili’s forever.   These insanely talented and well established scientists figured out how to use the CRISPR-Cas9 editing tool to turn a tomato into    a chili.

Capsaicinoids are what give peppers their heat and when these scholars of science mapped the tomato’s and chili’s genomes, they saw that the tomato has genes that, when transcribed, produce these spicy and hot capsaicinoids.

The reason why this is important is because the chili’s cultivation process is extremely tedious and requires many specific conditions, not to mention it having a small yield.  Since the yield of tomatoes is 30x that of the chili, using the CRISPR-Cas9 tool, they could change the shape and taste of the tomato to that of a chili. The price of a chili peppers, per kg, compared to tomatoes is roughly 60 cents higher. It may not seem a ton, but in bulk orders, it quickly adds up.

Lázaro E.P. Peres, who is aProfessor of Plant Physiology at the University of São Paulo and one of the scientists on the team, says, “The proof of concept here is that we can transfer the unique thing endemic to a less-produced plant into another plant that is more widely produced”.  The paper states the tomato “is highly amenable to biotechnological manipulation”. This would drive the price of the chili down which would help markets, restaurants, and Gardners worldwide.

The only issue to this is the publics opinion. For years, the already established “organic” companies having been labelling genetically modified food as unhealthy compared to non-GMO foods.  This claim is simply outright false.  “Any plant or animal product is full of DNA that our body readily digests, messing with one or two genes isn’t going to impact human health. The only way GM food could affect human health is if the modification somehow produce a protein product that was actively toxic to humans.”  This quote is from an article by the Genetic Literacy Project, which could be seen as having bias towards GMO foods, however their mission says,”is to aid the public, media and policymakers in understanding the science and societal implications of human and agricultural genetic and biotechnology research and to promote science literacy.”  All they are interested in doing is educating the public because so many people have been lied to by big organic corporations and the media to prevent customers from eating GMO products.  What would they have to gain by saying they are safe when they are not?    If the public can get passed the idea of genetically modifying foods, I believe turning a tomato into a chili pepper would save much money from hundreds of thousands of businesses– big or small.

What do you guys and gals think of GMO products?

For more information, please go check out the primary source of this article and the researchers report

 

 

Can a Fox Be Your New Pet?

The big difference between your dog and a wild animal is the relationship that it has with humans. For example, both dogs and foxes come from the canidae family, however foxes are generally scared of humans  while dogs are “ a man’s best friend”. So why is the fox’s response drastically different than a dogs?

 Scientists may have figured it out. The study was originally started in Russia where a scientist wanted to see if he could domesticate foxes like people had domesticated dogs. He started to breed silver foxes with domestic traits: ones that were more tamed and friendlier towards humans.  But at the same time he also bred foxes that were aggressive to humans in order to make an aggressive breed of foxes. He then started to compare the two breeds as the generations went on. He studied only 10 generations but 50 generations of silver foxes later Cornell did a study on the same foxes.

Cornell studied the tamed foxes’ brains in comparison to the fox’s brain that were aggressive towards humans.  The scientist obtained brain tissue samples from 12 tamed foxes and 12 aggressive foxes looking for differences between the two brains. The particular part of the brain they studied was the prefrontal cortex and basal forebrain which are known for processing more complex information. The prefrontal cortex processes social behavior and personality expression, while the basal forebrain is a critical component to processing memories. The neurotransmitters from those regions were what the researchers mostly focused on. In particular, they focused specifically on the neurotransmitters that release dopamine and serotonin in the foxes brains  which are responsible for feelings of happiness because they trigger the pleasure center of the brain.

Through the study of the neurotransmitters, the researchers found that genes from these sections of the brain from the tamed foxes were altered through the breeding of the foxes but not the ones that they expected.  The variant genes in fact coded for alterations in the  function of the serotonergic neurons and the glutaminergic neurons. Those neurons coincide with learning and memory. This shows that tamed animals learn and memorize differently than their aggressive equals.  Now that we know this do you scientists through genetic modifications will be able to tame or domesticate any animal by simply changing a gene in their brain?

Did You Know Plants Can Talk?

 

For thousands of years language has been a crucial part of cultures around the world, and a method unique to humanity of transmitting ideas, thoughts, emotions between us. Language has allowed us to work harmoniously together for our mutual improvement and survival. Recently, however, two researchers, Dr. Kim Valenta and her colleague Omar Nevo, have discovered that plants too, have developed their own unique and intricate method of conveying information to their pollinators; “the easier it is for fruit eaters to identify ripe fruits, the better the chance for both [, the plant and the fruit,] to survive.

The most vivid example of plant communication can be found in Madagascar’s Ranomafana National Park and Uganda’s Kiabale National Park where berry plants have evolved “to match each animal’s sensory capacities, [thus] signal[ing] dinner time in the jungle…” Dr. Valenta and Nevo analyzed the exact colors of each fruit with a spectrometer, and “with a model based on the visual capacities of the seed-dispersing animals, they also determined who was most likely to detect different fruit colors contrasting against an assortment of backgrounds.” The researchers concluded that “the colors of each fruit were optimized against their natural backdrops to meet the demands of the visual systems of their primary seed dispersers,” i.e. pollinators. Thus, red-green color-blind lemurs, in Madagascar were best able to detect the fruit with a blue yellow color scheme and monkeys and apes in Uganda, with tricolor vision like humans, were clearly able to distinguish red berries against a green backdrop.

Also recently discovered was that plants can communicate to their pollinators through scent. Dr. Nevo performed a scent-based study on the lemurs in Madagascar. His team collected various ripe and unripe fruits from all over the jungle of Ranomafana. “He suspected the leumur-eaten fruits would have a greater difference in odor after they ripened than the bird-eaten fruits.” To discover exactly how this scent-based communication worked, Nevo used the “semi-static headspace technique.” From this experiment it was confirmed that “fruits dispersed solely by lemurs produced more chemicals and a greater assortment of compounds upon ripening. It is now known that wild lemurs actually spend quite a lot of time smelling for the vivid difference in odor between ripe and unripe fruits in the jungle.

It is astonishing how plants have evolved over the years to be able to communicate with their pollinators for the betterment and expansion of their species. I would be interested to find out, what other organisms communicate (single cellular, multi-cellular, etc.) and what kind of information they find necessary to convey to others for their survival?

 

 

 

 

A Gene In Your Ears For Sour Taste?

Unlike the other four human tastes, our process of detecting sourness has always been a mystery, and scientists were definitely not expecting to find the answer in a  protein normally found in the inner ear.

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This protein, coded by the gene scientists refer to as Otop1, usually functions as part of the vestibular system to maintain balance. Given this more commonly known function of the protein, scientists were shocked to find its use for both balance and detecting the acids often associated with sour taste. The association is actually not as far- fetched as one might think. Otop1 codes for the synthesis of calcium carbonate crystals which rest on the hairs of the inner ear and detect gravity to help humans stand upright. Researchers found that the tongue also uses these crystals to detect sour taste. Calcium carbonate, a relatively basic compound, dissolves when it comes into contact with acid, which reaction can be detected by the brain and interpreted as sour taste.

How could such a protein find its way to use in both our senses of balance and taste?

The answer lies in evolution. If a certain protein proves advantageous over generations, organisms with it in surplus may evolutionarily find other uses for the it. Recently scientists have actually found several proteins for sensory organs that double as homeostatic sensors in other tissues. Otop1 is only one of many; smell receptors are found in the kidney in surplus, as are sweet taste receptors in the bladder.

Although we have unearthed a lot about the human body over the years, there is always so much more to learn!

Fighting the mosquito disease problems with… mosquitos?

Since the discovery of CRISPR-Cas9 system (Clustered Regularly Interspaced Short Palindromic Repeats), gene editing has become a highly debated topic. One of the reasons backing the use of CRISPR-cas9 is to prevent diseases. These diseases include mosquito-borne diseases such as zika, dengue fever, and malaria.  Malaria in particular kills around 3,000 children every year. Various groups of scientists have worked on genetically modifying mosquitos to stop the spread of malaria by making female offspring sterile and unable to bite, making male offspring sterile, or making mosquitos resistant to carrying diseases. A point of concern was if the modified gene would stay relative and would carry from generations. In order to make offspring, genes from both parents must be used, resulting in the offspring carrying the modified gene only half the time.  In particular cases, mutations would occur in the altered DNA, which nullified the genetic changes.  This has been solved by developing a gene drive, which makes the desired gene dominant and occur in the offspring almost 100% of time.  This entails almost the entire mosquito population could have this modified gene in as little as 11 generations.

Image by Author

Recently, the government of Burkina Faso, a small land-locked nation in west Africa, has approved for scientists to release mosquitos that are genetically modified anytime this year or next year.  The particular group of mosquitos to be released first is a group of sterile males, which would die rather quickly.  Scientists want to test the impact of releasing a genetically modified eukaryotic organism in the Africa. It is the first step in “Target Malaria” project to rid the region of malaria once and for all.

 

One of the major challenges in gaining allowance to release the genetically modified species was the approval of the residences, who lack words in the local language to describe genetics or gene editing.  Lea Pare, who leads a team of scientists modifying mosquitos, is working with linguists to answer questions the locals may have and tp help develop vocabulary to describe this complex scientific process.

What do you think about gene editing to possibly save millions?

Read the original article here.

View a video explaining how scientists can use genetic engineering to fight disease here.

Closer to Reality: Gene Editing Technology

In August of 2017, scientists in the United States were successful in genetically modifying human embryos, becoming the first to use CRISPR-cas9 to fix a disease causing DNA replication error in early stage human embryos. This latest test was the largest scale to take place and proved that scientists were able to correct a mutation that caused a genetic heart condition called hypertrophic cardiomyopathy.

CRISPR-cas9 is a genome editing tool that is faster and more economical than othe r DNA editing techniques. CRISPR-cas9 consists of two molecules, an enzyme called cas9 cuts strands of DNA so pieces of DNA can be inserted in specific areas. RNA called gRNA or guide RNA guide the cas9 enzyme to the locations where impacted regions will be edited.

(Source: Wikipedia Commons)

 

Further tests following the first large-scale embryo trial will attempt to solidify CRISPR’s track record and bring it closer to clinical trials. During the clinical trials, scientists would use humans- implanting the modified embryos in volunteers and tracking births and progress of the children.

Gene editing has not emerged without controversy. While many argue that this technology can be used to engineer the human race to create genetically enhanced future generations, it cannot be overlooked that CRISPR technology is fundamentally for helping to repair genetic defects before birth. While genetic discrimination and homogeneity are possible risks, the rewards from the eradication of many genetic disorders are too important to dismiss gene editing technology from existing.

 

The Weirder Side of CRISPR

If you’ve been following science news at all, you’ve heard of CRISPR, the gene-editing tool which is rapidly becoming a very hot topic. Since its discovery, CRISPR has been used for some truly extraordinary things. It’s also done some other things, which stray from medical miracles into the realm of the strange.

Alphr.com reports some of the weirder projects using CRISPR. This includes manufacturing super-dogs, as well as the possibility of bringing back the woolly mammoth! This is all being done as you read this through CRISPR CAS-9

Another project mentioned in the article is an effort to create organs in pigs suitable for human transplants. This has become a larger topic of conversation, as there is always an ample need for organs, and if this project comes to fruition, waiting lists for organ transplants could possibly be abolished completely.

To read the other weird projects using CRISPR right now, check out the article.

Comment below your thoughts on this article, and the uses of CRISPR in general. I, for one, would love to see a mammoth before my own eyes!

Crispr-Cas9 is the gateway to a new frontier in genetic engineering. Here’s The good and the bad.

For a number of years now, molecular biologists have been diving increasingly further into the field of genome editing. The latest development into the field is the emergence of CRISPR-Cas9. CRISPR-Cas9 has risen to prominence over other potential methods of genome editing due to its relatively simple construction and low cost. CRISPR-Cas9’s original primary and intended purpose was to help fix mutations within DNA, and with this it could theoretically help eradicate entire diseases. This application of CRISPR is wholly positive, however with the increasing prevalence of the technique other potential uses have been discovered, and some of these potential uses raise profound ethical questions.

One of the main concerns of people skeptical about CRISPR is their assertion that once the door to the wholesale genetic editing of offspring is open, there is no going back. This, on its own, is a reasonable concern. The ability to choose a child’s sex, eye color, hair color and skin complexion is very likely to be made available to by CRISPR in the coming years. CRISPR does not yet have the capability to influence more abstract elements of the genome, such as intelligence and athletic ability, but this may not be far off. There are legitimate concerns that this is a slippery slope towards a dystopian society similar to the one seen in the movie Gattaca, where society is stratified into two distinct classes: those who are genetically engineered and those who are not.

Another concern raised by some scientists is the overall safety of genetic editing. A potentially very hazardous negative result of CRISPR is the possibility of an “off target mutation.” An off target mutation is the result of CRISPR mutating something other than the intended part of the genome and it could have disastrous consequences. Now, many scientists believe that with further advancements in the field the likelihood of something like an off target mutation occurring could be reduced to almost zero. However, it is important to examine the risks of any new process, and the prospect of something like an off target mutation occurring is certainly noteworthy.

For more information click here.

Inside Out

CRISPR is a revolutionary tool used for editing the human genome. It allows for the altering of  any given DNA sequence and ability to modify any one specific genes’ function. Its applicability consists of correcting genetic defects, treating and preventing the spread of diseases, and improving crops. However, it also raises some ethical concerns, that of which mainly is the idea that practicing CRISPR technology could be considered as playing the role of “God”.

CRISPR was adapted from the natural defense mechanisms of bacteria, which use CRISPR-derived RNA and Cas proteins, to prevent attacks by viruses and other intruding organisms. They do so by chopping up and destroying the DNA of the virus. When these components are derived and applied to more complex, organisms, it allows for the manipulation of genes.

Disregarding its ethical concerns, CRISPR can provide substantial support to a previously uncharted area of medicine; the diagnosing and treating of genetic disorders, which was previously thought to be that if one had a genetic disorder it would be incurable.  Clinical trials are set to take place both in Europe and in North America, where patients with rare genetic disorders will give cellular samples in an attempt to alter their genome, implant them back into the individual, and hopefully cure the genetic abnormality.

With CRSPR taking such progressive strides in the past year, it is not outrageous to predict what its usage could end up providing society with.  With the ability to edit the human genome there are endless possibilities in which science could evolve this area of study to benefit the human race.  CRISPR can even be used to boost the expected intelligence of an embryo.  Who knows, thirty years from now we could be watching the news and hear of the first ever “superhuman”, a genetically modified human that has been hand-coded for optimality in all human functions.

CRISPR-cas9: Coming to a Human Near You

CRISPR

What is CRISPR?

As the world becomes more technologically developed, CRISPR is a new and upcoming technique to genetically edit genes. Being able to alter DNA sequences and revise gene roles, scientists now have the ability to correct defects, prevent diseases/mutations and improve genes overall.  As time goes on, scientists now feel that they are ready to genetically alter humans.

This image represents what CRISPR is capable of. The two wrenches represent that CRISPR edits the DNA strands and creates new and improved DNA.

How does CRISPR work?

CRISPRs are specialized stretches of DNA recognized by the protein Cas9. Cas9 is an enzyme that acts like a pair of molecular scissors, capable of cutting strands of DNA. Without that enzyme, CRISPR would not be successful.

CRISPR stands for “clusters of regularly interspaced short palindromic repeats.” It is a specialized region of DNA with two obvious characteristics

  1. the presence of nucleotide repeats and spacers.
  2. Repeated sequences of nucleotides — the building blocks of DNA — are distributed throughout a CRISPR region.

Spacers are bits of DNA that are interspersed among these repeated sequences.

***According to livescience.com, there is a built-in safety apparatus, which guarantees that Cas9 will not cut anywhere in a genome. Short DNA sequences become tags and stay adjacent to the target DNA sequence. If the Cas9 complex doesn’t see a short DNA sequence next to its target DNA sequence, it won’t cut.***

Is this really safe for humans?

Not too long ago, a study by Columbia University Medical Center was published in May, in the journal Nature Methods, about this “revolutionary” CRISPR gene-editing technique. It claimed that CRISPR caused unwanted and dangerous mutations and left the medical community baffled. The paper questioned how effective gene-editing technology is and called for a reassessment of the technique’s safety. However, this publication has to do with how CRISPR was first tested: 3 mice and very controversial results. Editage.com stated that “two of the three study subjects, the CRISPR-edited mice, happened to be more closely related and thus shared more mutations. Therefore, the paper claimed that “the premise of the old study was incorrect.”



If you have the choice, will you use CRISPR to design your children? Comment!

Hacking Evolution to Stop Malaria?

Kevin Esvelt is a biochemist, at MIT Media Lab, his approach to dealing with disease is instead of waiting for a disease to infect you, eradicate it completely. His hope is that on animals, such as mosquitos. he could use the CRISPR technology to block the gene. He believes that “we should be able to build organisms that are programmed to be immune to every virus known to infect them“.  By using the CRISPR/Cas9 gene editing and gene drive he, and his team, would be able to block that gene from appearing in the next generation.

C

 

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Although, eradicating horrible diseases such as Ebola and Malaria sounds extremely beneficial; there is some draw back. Malaria, for example, is spread across many nations; therefor, scientist would need permission to genetically alter a species from each nation; but before this can be agreed upon test communities would need to be set up. Esvelt would want to test the CRISPR technology in small, localized areas before moving on to an entire species. Esvelt is confident that with a disease as deadly as Malaria, nations would be able to reach an agreement to go with gene editing. Esvelt hopes that by using CRISPR technology he would be able to create organisms, like mosquitos, in the case of Malaria, that are programmed to be immune to Malaria. If this were to happen these deadly disease would not be able to spread. Hence, Esvelt’s key belief of not waiting for the disease infect you, but rather eradicate it completely,

 

 

Build A Baby?!

Have you ever wanted a baby to be a super fast swimmer like Michael Phelps? How about a child who has more talent than Mozart? Well, that can’t happen.

According to the  New York Times Article, Scientists in Oregon have successfully modified the DNA of human embryos. This led to the new hope that designer babies are in our near future. But, designer babies are more likely to be seen in movies than in reality.

The main reason why designer babies are unlikely is because great vocals and amazing coordination does not come from a single gene mutation, or even from an easily identifiable number of genes.

Hank Greely, director of the Center for Law and the Biosciences at Stanford, said,“Right now, we know nothing about genetic enhancement,”. “We’re never going to be able to say, honestly, ‘This embryo looks like a 1550 on the two-part SAT.’”File:Baby Face.JPG

Physical traits, like height or arm length, will also be difficult to genetically manipulate. Some scientists estimate height is influenced by as many as 93,000 genetic variations. A recent study identified 697 of them.

Talents and traits aren’t the only thing that are genetically complex. So are most physical diseases and psychiatric disorders. The genetic message is not a picture book ,but it actually resembles a shelf full of books with chapters, subsections and footnotes.So talents, traits and most medical conditions are out of the equation.

But about 10,000 medical conditions are linked to specific mutations, including Huntington’s disease, cancers caused by BRCA genes, Tay-Sachs disease, cystic fibrosis, sickle cell anemia, and some cases of early-onset Alzheimer’s. Repairing the responsible mutations in theory could eradicate these diseases from the so-called germline, the genetic material passed from one generation to the next. No future family members would inherit them.

Although this is challenging, it is proven to be more possible for scientists to alter the genes that lead to genetic diseases.

Last but not least, it is illegal.
There are debates regarding ethics and “playing God”. “I’m totally against,” said Dr. Belmonte. “The possibility of moving forward not to create or prevent disease but rather to perform gene enhancement in humans.”

Other people are scared of a super children takeover.

“Allowing any form of human germline modification leaves the way open for all kinds — especially when fertility clinics start offering ‘genetic upgrades’ to those able to afford them,” Marcy Darnovsky, executive director of the Center for Genetics and Society, said in a statement. “ We could all too easily find ourselves in a world where some people’s children are considered biologically superior to the rest of us.”

In summary, genetic modification for babies will only be used in dire cases. Therefore, the only way I can have a red head child who can play the piano and the flute simultaneously with their feet is through Sims 4.

Tree Lobsters Are Back!

Image result for Stick insects Tree lobsters Lord Howe

Lord Howe Tree Lobster

Tree Lobsters are actually not lobsters at all. Nor are they crustaceans.  They are actually just insects with a similarly shaped exoskeleton. But that’s not what makes them interesting. What does, is that Tree Lobsters have seemingly come back from extinction.

The Species, originally from the Lord Howe Island in the Tasman Sea between Australia and New Zealand, went extinct during the 1920’s due to becoming the main food source for an invasive rat species that came onto the island. The Tree Lobsters were only formally declared extinct in 1960 though. Since then scientist had pretty much forgotten about them.

Image result for Stick insects Tree lobsters Lord Howe

Ball’s Pyramid Stick Insect

Thus, when scientists found a small group of stick insects similar to Lord Howe Tree Lobster’s on Ball’s Pyramid, a volcanic stack 12 miles away from Lord Howe Island, in 2001, they were quite surprised. The Ball’s Pyramid stick insects were skinnier and darker but scientists were still hopeful the newly discovered insects were, in fact, the same species as the extinct Lord Howe Tree Lobsters. Scientists tested the genes of the stick bugs from Ball’s Pyramid with genes extracted from preserved Lord Howe Tree Lobsters and found out that despite some morphological variance, they are still the same species. They speculate that diet, age, and environment had caused the Ball’s Pyramid Stick Insects to look a little different. How the species got to the volcanic stack is still a mystery as the insects cannot swim but they infer that they had been carried over by birds.

The newly discovered Tree Lobsters are now being bred at the Melbourne Zoo and elsewhere in an attempt to reintroduce the species to Lord Howe Island. However, the invasive rat species on Lord Howe Island still remains a problem as it threatens the lives of over 70 different native species. In order to successfully reintroduce the Tree Lobsters back to Lord Howe, the rat problem needs to be taken care of first.

How A Chemical From the Cypress Tree Could Advance Epigenetics Against Cancer

by Czechmate on Wikimedia Commons

Found in the essential oil extracted from the bark of a cypress tree, a chemical named hinokitiol shows potential to impact epigenetic tags on DNA and stop the activity of genes that assist the growth of tumors.

In order to develop an of understanding cancer, researches have had to comprehend the DNA methylation, an epigenetic function which controls gene expression. In regular DNA methylation, genes that work to fight against tumors are turned on, reducing the risk of cancer. However, if DNA methylation is negatively altered, then those cancer-fighting genes will be silenced, helping to progress cancer development. Scientists have tried to combat irregular DNA methylation and over-silencing of genes by creating epigenetic anti-cancer medications that reverse non-beneficial methylation effects. Like in most cases of medication usage, the users face unappealing side effects. Hinokitiol is attractive to scientists because it is a natural compound with many health benefits and way less side effects than modified drugs that can possibly cause mutagenesis and cytotoxicity.

 

Researchers from the Korea University College of Medicine tested the productivity of the hinokitiol chemical in a study by giving doses of it to colon cancer cells. It was found that this chemical helped to inhibit the colon cancer cells efficiency without affecting the colon cells without cancer. The scientists also found through careful inspection that the presence of hinokitiol decreases the expression of proteins DNMT1 and UHRF1; both of which are proteins that encourage carcinogenesis. In summary, the doses of hinokitiol appear to have allowed normal cells to remain healthy, while reducing the ability for the colon cancer cells to thrive and ceasing the production of proteins that promote cancer maturation.

Researchers are continuing their search for natural compounds, as opposed to artificial medications, that can prevent the flourishing of cancer in our bodies through playing a positive role in gene expression and DNA methylation.

http://www.whatisepigenetics.com/cypress-trees-epigenetically-protect-cancer/

 

 

https://commons.wikimedia.org/wiki/File:Raindrops_on_leyland_cypress.jpg

Preferential Gene Expression: Not As Random As We Thought

Our conventional knowledge of genetics dictates that the activation of genes in our DNA is random. It is equally likely that our body will express our mother’s alleles as it is that our body will express our father’s. In the case that one parent donates a defective copy, it will be silenced; the other parent’s healthy set of DNA takes precedence and becomes activated.

However, a new study indicates that gene expression and activation is not as random as we thought. In certain regions of the body, our genes demonstrate preferential expression.

A team of scientists at the University of Utah found that almost 85 percent of genes in juvenile mice brains displayed preferential treatment. The mice brains activated one parent’s set of DNA over the other’s. This phenomenon was observed in other areas of the body, as well as in primates.

Although the preferential expression came to a close within ten days, it could provide explanations for vulnerability to brain diseases such as schizophrenia, ADD, and Huntington’s. The temporary preferential treatment to one parent’s copy of DNA could trigger a host of problems specific to that cell site that lead to such disorders, if the parent had given a defective copy of genes.

The study has the potential to alter our basic understandings of genetics, and how we are more prone to certain specialized diseases.

Image: (Public Domain, https://pixabay.com/en/dna-biology-medicine-gene-163466/)

The Grey Area of Human Gene Editing

The process of Human Gene Editing developed with the goal to prevent future generations from suffering from genetic diseases present in past generations, like our own. Human gene editing, provided it is done only to the correct disease, alters the DNA in embryos, eggs, and sperm to the when reproduction occurs, the gene for the disease or disability is not inherited. However, two weeks ago the National Academies of Sciences and Medicine issued a report stating that human gene editing is being used to enhance people’s health or abilities. This is considered unethical according to organizers of a Global Summit on human gene editing.

Human gene editing has been given a “yellow light” because the process is not yet approved to be done on people. There are high hopes that diseases caused by only 1 genetic mutation such cystic fibrosis and Huntington’s disease will be eliminated due to this process. Unfortunately diseases that are caused by more than one genetic mutation, such as autism or schizophrenia, are not curable by this process.

National Cancer Institute

Gene Editing on humans is such a controversial topic right now: is it ethical to change genes? should the practice be used to change physical appearances? Ultimately, if Human Gene Editing is approves, who decides when it becomes too much, or unethical. This grey area is presented to be somewhere between when it is appropriate to help aid the life of a human, ridding them of a disease, and when enhancements are made.

 

Is There a Limit to How Old Humans Will Get?

In the 1900s, the life expectancy for humans in the United States was approximately 50 years. Since then, the age to which humans can live has only grown. In 1997, a woman by the name of Jeanne Calment died at the age of 122- an astounding increase from the life expectancy less than a hundred years ago. A new study written about in the New York Times explains that Dr. Vijg, an expert on aging at the Albert Einstein College of Medicine, feels that we have now reached our “ceiling. From now on, this is it: Humans will never get older than 115.” Dr. Vijg and his graduate students published their pessimistic study in the journal Nature, presenting the evidence for their claim.

For their study, Dr. Vijg and his colleagues looked at how many people of varying ages were alive in a given year. Then they compared the figures from year to year, in order to calculate how fast the population grew at each age. For a while, it looked as though the fastest-growing group was constantly becoming older; “By the 1990s, the fastest growing group of Frenchwomen was the 102-year-olds. If that trend had continued, the fastest-growing group today might well be the 110-year-olds.” (NY Times Article). Instead, the increases slowed and eventually stopped, leading Dr. Vijg and his colleagues to conclude that humans have finally hit an upper limit to their longevity. Further research into the International Database of Longevity seemed to validate their findings; No one, except in rare cases like Ms. Calment, had lived beyond the age of 115. It appears as though human beings have hit the ceiling of longevity.

There was a varied mix of responses to the study. Some, like Leonard P. Guarente, a biology professor at MIT, praised it, saying “it confirms an intuition he has developed over decades of research on aging.” Others, like James W. Vaupel, the director of the Max-Planck Odense Center on the Biodemography of Aging, called the new study a travesty and said, “It is disheartening how many times the same mistake can be made in science and published in respectable journals.”

This study is by no means conclusive. It is simply one more piece of research in the ongoing debate over whether human beings will continue to live longer, and will continue to be debated by many experts in the field.

However, one must wonder whether living longer should be the goal. After all, as Dr. Vijg pointed out, “aging is the accumulation of damage to DNA and other molecules. Our bodies can slow the process by repairing some of this damage. But in the end, it’s too much to fix. At some point, everything goes wrong, and you collapse.” While morbid, he makes a valid observation: Humans can only go so long until necessary bodily functions begin to break down. Rather than worrying about whether we will live to an extraordinary age such as Ms. Calment, I concur with Dr. Vijg; the focus should be on living the most amount of healthy years and taking care of our bodies. While it may seem like a great idea to live to the age of 125, what good would that do if you aren’t able to continue with the activities you enjoy because your body is breaking down?

 

Other Relevant Articles:

In Depth Explanation of Longevity: https://en.wikipedia.org/wiki/Longevity

A brief summary of Dr. Vijg’s findings (a bit shorter than the NY Times article): http://www.newser.com/story/232121/human-lifespan-has-likely-maxed-out.html

An interesting article about an entrepreneur’s quest to make people live even longer: https://www.theguardian.com/science/2015/jan/11/-sp-live-forever-extend-life-calico-google-longevity

 

CRISPR/Cas9 Provides Promising Treatment for Duchenne Muscular Dystrophy

There are nine kinds of muscular dystrophy and of these, Duchenne MD is the most common severe form of childhood MD. It affects about 1 in 5000 newborn males, only in very rare cases has it affected females. DMD is a genetic disorder that causes progressive muscle degeneration and weakness. Patients usually die by age 30 to 40.

DMD is caused by the absence of a protein, dystrophin, that helps keep muscle cells intact. In 1986 it was discovered that there was a gene on the X chromosome that, when mutated, lead to DMD. Later, researchers discovered that the protein associated with this gene was dystrophin. From this information, we can tell that this disorder is sex-linked, which explains why women are mainly carriers.

No one has found an absolute cure for this genetic disorder until now. Even in recent years, people have discovered treatments that will make patients’ lives more bearable, but never reverse the disorder. As a result of these advances, mostly in cardiac and respiratory care, patients are able to live past teen year and as long as in to their fifties, though this is rare. Although there are still drugs being tested like Vamorolone (a “dissociative steroid,” is an anti-inflammatory compound), more treatments on the molecular level are now being considered. However, thanks to recent discoveries and research with the new genetic technology, CRISPR/ Cas9, scientists may have found a treatment for DMD.

This new approach to gene correction by genome editing has shown promise in studies recently. This particular correction can be achieved in a couple ways: one is by skipping exon 51 of the DMD gene using eterplirsen (a morpholino-based oligonucleotide). Studies over four years show prolonged movement abilities, and a change in the rate of decline compared to controls. The newest approach to gene correction using CRISPR/Cas9, which the article I’m writing about focuses on, was performed in this study as next described: the CRISPR/Cas9 system targets the point mutation in exon 23 of the mdx mouse that creates a premature stop codon and serves as a representative model of DMD. Multiple studies in three separate laboratories have provided a path and laid the groundwork for clinical translation addressing many of the critical questions that have been raised regarding this system. The labs also discovered by further demonstrations, that this is a feasible treatment for humans. Functional recovery was demonstrated in the mice, including grip strength, and improved force generation- all of which are very important and hopeful discoveries. It is estimated from these studies that this new method will pass clinical trials and go on to benefit as many as 80% of DMD sufferers. Even greater success rates are expected if this is performed in young and newborn DMD patients.

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