BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: genetics (Page 4 of 4)

New Deadly Virus Discoved in Africa

Recently an article was released summarizing the discovery of a new disease in Africa. In 2009 a fifteen year old boy in a small village in the Democratic Republic of the Congo fell ill. The initial symptoms were malaise and a bloody nose, but quickly the boy developed an acute hemorrhagic fever. Within two days of the showing symptoms the boy died. Approximately eleven days later a thirteen year old girl who went to the same school as Patient One developed similar symptoms, and died three days later. At the local health center which both Patients One and Two visited, a thirty-two year old male nurse began to experience identical symptoms. He was moved to the hospital in Boma, Democratic Republic of the Congo, where the doctors drew blood and began to test for known viruses; they found nothing. However, very recently a research team used deep sequencing to determine the pathogen,which they dubbed “Bas-Congo Virus”, and posted their results in the Public Library of Science Journal. It was discovered that the virus belonged to the Rhabdoviridae family, best known for the Rabies virus. Interestingly enough, though, the Bas-Congo virus only shares 34% of the amino acids found in other Rhabdoviruses, meaning that it is very different. The discovery of this virus may end up being of great importance due to the possibility that the virus may return. In any case, we will have one less pathogen on this planet to identity lest there be another, more deadly, outbreak.

Identical but Not the Same

 

Some Rights Reserved. More Information: http://www.flickr.com/photos/timoni/3390886772/sizes/s/in/photostream/

After studying genetically inherited traits and diseases it could be easy to assume that genes determine everything about us. While it is true that colorblindness is a sex-linked trait – there is certainly more to the story.

Monozygotic “identical” twins are genetically identical, so they should be the same in all ways shouldn’t they?

Why, then, does one twin get early onset Alzheimer’s disease and the other “identical” twin doesn’t? The same is true for height, autism, and cancer. Although, when one twin has a disorder the other is more likely to get the disease also, that is not always the case.

In the January edition of National Geographic, author Peter Miller discusses the newest theories about how genes, environoment and epigenetics affect our life (and the end of it).

Twins offer scientists a unique opportunity to study how genetically identical people differ. Basically, that means scientists can study how things other than genes affect human development and lifespan. Already, scientists have found that a persons height is only 80% determined by genetics because the heights of “identical” twins differ by about .o8 on average. Using IQ tests, scientists have nearly disproved John Locke’s Tabula Rasa or blank slate theory (the idea that children are born with a blank mind that is either stimulated – (and made intelligent) – or not –  (kept unintelligent)). Specifically, scientists studied twins who had been separated at birth and adopted into different families. In this way, scientists have found that intelligence  is about 75% controlled by genetics.

So that leads to the question, what is it besides genes that affects us humans so drastically?

Environment has something to do with our differences. However, that cannot be the whole story. “The Jim Twins” as they are called in the twin science community, were studied in the 1870’s. They were adopted into different families where both boys were named Jim. Then went on to have the same jobs, marry wives of the same name (two Lynda’s first then two Betty’s), enjoy the same hobbies, enjoy the same brand of cigarette and beer, name their sons James Allan and James Alan… the list goes on. These two lived very similar lives, yet they grew up in very different environments. If environment isn’t the only factor in creating difference then what is?

Scientists have recently come to believe that epigenetics plays a significant role in our lives. Epigenetics (site 2) can be seen as the meshing of environment and DNA. In the words of author Peter Miller “If you think of our DNA as an immense piano keyboard and our genes as keys – each key seach key symbolizing a segment of DNA respinsible  for a particulare note or trait, and all the keys combining to make us who we are – then epigenetic prcesses determine when an how each key can be struck changing the tune.”  Environmental changes do have some impact.  When a pregnant mouse is put under stress during the pregnancy it can create changes in the fetus that lead to abnormal behavior as the rodent grows into adulthood.

However, scarily enough, many epigenetic changes appear to occur randomly (thus creating a probelm for the organized nature/nurture theory). Currently work is being done studying DNA methylation, which is known to make the expression of genes weaker or stronger. Specifically, Andrew Feinburg, director of the Center for Epigenetics at Johns Hopkins School of Medicine, is working to find how DNA methylation relates to autism. Currently, he is using scanners and computers to search samples of DNA from autistic twins who have the disease in varying degrees. He is looking to compare how and why

the genes are expressed differently.

In the end, all we know is that there is more to our future than our genes can tell us. Yes, our genes play a huge role in who we are as people – in terms of appearance, character, intelligence and more – but there are some variables that our environment and epigenetics control.

Main Article: Miller, Peter. “A Thing or Two About Twins.” National Geographic. Jan 2012: 38-65. Print.

Wait, Babies can be Born Without Eyes?

This picture displays a baby with healthy eyes!

This photo was found on blogs.smarter.com through Google Advanced Search

I always knew individuals could lose eyes if a terrible accident occurs, but I never knew that babies can be born without eyes! Did you?

Recently, a condition called anophthalmia has been discovered. It is when there are complications with the development
of both copies of the STRA6 gene, one that is “responsible for transporting vitamin A into the cells.” In fact, vitamin A is needed for the development of every inch of our retina, a tissue lining the inside of the eye. In less scientific terms, anopthalmia is when an individual is born with the loss of one or both eyes. Microphthalmia, a condition where an individual has small eyes, and coloboma, which is a deformed eye, are two other eye conditions that develop in a baby while he or she is still in the womb. These three diseases make up eleven percent of all eye deformations. However, the Micro & Anophthalmic Children’s Society UK reported that microphthalmia and coloboma are much more common than anopthalmia.

Doctors like Dr. Sean Ennis from the UCD School of Medicine and Medical Science, University College Dublin, and the National Centre for Medical Research started researching the perplexing idea that babies can be born without eyes with “nine individuals from across several generations of an Irish ethnic minority family of nomadic descent who suffer with one or more of the three eye defects to varying degrees of severity.”
Dr. Ennis says,

 

“Using advanced gene sequencing technologies, we firstly scanned for regions of DNA shared by all patients before analysing a single common region for the disease gene. From this we pinpointed STRA6, a gene responsible for transporting vitamin A into cells.

 

In the past, doctors have found that alterations and complications of the STRA6 gene in DNA can cause Matthew-Wood syndrome. This is a disease that can cause irregular eye formation and hardships for development in general.
Scientists of the University College Dublin, Ireland, in addition to doctors such as Dr. Hui Sun and Dr. Riki Kawaguchi of the University of California, actually made this fascinating discovery recently. Now, they are attempting to make genetic testing to determine whether a baby in a mother’s womb will have anopthalmia early on. They would really like to develop a clinical practice, which would take place at the National Centre for Medical Genetics (NCMG) in Dublin. Professor Andrew Green of University College Dublin says,

“Accurate carrier testing and genetic counselling can be offered to those individuals planning to have children. And ultimately, this work may be used to develop preventive measures or possible treatments in the future,”

As of right now, babies born with small eyes, deformed eyes, or no eyes must get prosthetic eyes to help them see and help the development of other parts of their bodies, including the face and skull. Eye defects can also be associated with birth defects and deformations in the heart, lungs, and diaphragm. We must hope for progress in the research and clinical trials for anophthalmia, so that the malformation and lack of eye disorder disappears forever one day!

Could there be another reason?

From Chris Berwick's blog- White blood cells amongst red blood cells

Leukemia has always been a tough form of cancer to combat. It is the leading cancer found in children and can also be found in adults. Leukemia “is a cancer of the blood or bone marrow (which produces blood cells). A person who has leukemia suffers from an abnormal production of blood cells, generally leukocytes (white blood cells).”

In this specific case, long island doctor Steven Allen had a patient with cell leukemia. Cell leukemia is a rare form of leukemia and usually has fatal results within 6 months. Recently Dr. Allen’s patient died after just three months after she was diagnosed.

Cell leukemia is rarely treatable because most patients have a genetic mutation in a gene called KIT. This gene refutes any type of drug that is typically used on patients with leukemia. The phenomenon about Dr. Allen’s patient in particular case is that she did not have this genetic mutation on KIT, but her body still would not accept any drug, which resulted in her early death.

With her death came two discoveries that were ground breaking in the cure for leukemia. Researchers at Cold Spring Harbor Laboratory have found two other gene mutations that refute the other drugs that have recently been studied as a cure for people with mast cell leukemia with a mutation on the gene KIT.

While Dr. Allen remains confident that this is going to change the direction of cures for leukemia, his colleague said “We must reallykeep in mind this was a single case study and we have to follow it up with many other studies.” These studies will help  “prove the mutations are present in other patients.”

What still confuses me is: if these mutations are the cause of mast cell leukemia, are there other mutations we have not yet discovered in all other forms of  cancer. If this be the case how do we know that the drugs we are using are not just a waste of time. Maybe it would be better for doctors to understand all gene mutations leading to each persons specific type of cancer before rushing into one form of treatment that has worked on others. Besides aren’t all humans different?

photo credit: angleys82

Sources: http://www.newsday.com/news/health/li-researchers-make-leukemia-discovery-1.3400035

http://www.medicalnewstoday.com/articles/142595.php

http://en.wikipedia.org/wiki/CD117

Monkey Be, Monkey Do

Are you one of those people who has always wondered about scientist’s progress in creating genetically amalgamated Monkeys? Well, if the answer is yes, then you need wonder no more, because Scientists have recently created their very own combinations of primate genes known as Chimeric Monkeys through the extensive study of stem cells and embryonic tissue.

The term Chimeric Monkey, stemming from the Greek Chimera, essentially describes the scientists efforts of combining various monkey genes in a prospective embryo, and empregnating a mother with said genes to direct what the eventual monkey child will develop into based on its new genes. It should be noted also that experiments with chimeric mice have also been a great asset in this venture, as they have provided certain genes which serve as “knock out” genes for  ones that the scientists wish to delete when creating the new monkey genome.

Shoukhrat Mitalipov of the Oregon National Primate Research Center at Oregon Health & Science University has been one of the primary figures in researching this new breakthrough chimeric studies saying that “The possibilities for science are enormous.” The basic procedure for creating the Chimeric monkeys entails the initial mixing of embryonic cells very early in their development that are classified as totipotent, or still having the capability of creating an entire animal with placenta, and other life sustaining tissues. Mitalipov has stated that “The cells never fuse, but they stay together and work together to form tissues and organs”.

So what do you all think? Is this all really a huge breakthrough in genetic science, or perhaps going a bit too far in what we were meant to manipulate?

Oh, and by the way, Mitalipov emphasized that there is no need or plans for chimeric humans,  just in case you were wondering

Tasting Colors?!

Credit: Carly Bodnar

Last year while doing a practice SAT reading section, I came across a story about a condition called synesthesia. If you have never heard of it before, you’re not alone. Synesthesia is a very rare, sense-mixing condition in which people taste colors or see smells. Sounds crazy, right? According to studies, 3% of the world population claim that they experience some form of synesthesia. I couldn’t believe it! I didn’t understand how people could taste and see intangible things.

A recent study shows that there is a pattern among people who have the condition that close family members have similarly entangled senses. Scientists have examined several genes to see which ones contribute to the phenomenon. Scientists hope that the uncovering of the condition’s genetic basis might reveal why it occurs and potentially help develop cures for similar neurological diseases.

The study, led by neuroscientist David Eagleman, studied a region of chromosome 16, the chromosome believed to hold the gene responsible for synesthesia. Eagleman and his colleagues believe that a defect in this gene may blend connections in the brain, leading to insufficient regulation of the brain’s neural bridges. David Brang from the University of California, San Diego explains, “It could be that everyone is born with global connectivity in the brain, and over time most undergo a refining process.” Another theory proposes that synesthesia is caused by a shift in the brain’s balance of chemicals. This hypothesis is supported by the fact that people can have synesthetic experiences if they take hallucinogens.

Eagleman believes that the continued study of synesthesia could more clearly illustrate how genetic changes affect changes in brain function. Finding more information about synesthesia can help uncover how different brain areas interact with each other. The discovery of neurological networking problems could also help find cures for or advancements in other degenerative neurological and genetic diseases. So for those of you who didn’t believe that such a condition existed, it does! Keep in mind, though, that these types of diseases often have genetic origins, another reason why there is not that much information on these obscure diseases. However, at a time when advancements and discoveries in genetics are so prevalent, Eagleman is confident that more information about this condition will be uncovered soon. Remember, next time you are doing a SAT reading section, don’t forget about the information given in those stories, they could give you insight into potential scientific discoveries!

I Got it From My Mama . . . and My Papa

Photo Credit: By Me

Ever wonder why Justin Timberlake could belt it out or how come Usain Bolt is so fast? Well the answer’s pretty unexpected, but not too surprising: genetics. Now while genetic prowess is not the sole key to these superstars’ successes, recent studies have shown that certain genes are attributed to superior athletic performance and feel of rhythm.

Recent studies have show that babies are born something called beat induction, the ability to follow a beat. Prior to this study, it was thought that basic music skills like rhythm were solely learned or an offshoot of language. However, scientists were able to study two and three-day-old babies’ reactions to changes in rhythms and they found that babies brains experienced  a momentary disturbance, known as a mismatch negativity (caused by the failure of an expected stimuli to occur), when the beat changed. It was impossible that the newborns could have learned beat induction in a few days, so it was obvious that it is an ability passed down genetically. Beat induction is a relatively new genetic trait , one only found in humans; even our closest primate relatives do not have this skill. It is even thought that beat induction may have been an adaptation gained to help humans with conversational communication.

Geneticists have been doing more and more groundbreaking research about the connection between inherited traits that may cause offspring to be more athletic or suited for competition at a higher level. For example, in 2003 Australian geneticists identified a gene called Actinen A (ACTN3), which codes for a protein that helps build fast-twitching muscles and muscle fibers that move with greater force, thus speeding up leg movement. The more fast twitching muscles an athlete has, the better they are at burst energy sports like sprinting, football, and baseball. Recent reports show that 70% of Jamaicans have the ACTN3 gene, which could explain Jamaican sprinters like Usain Bolt’s success at the 2008 Beijing Summer Olympics. Similarly, Olympic swimming champion, Michael Phelps, may have also inherited advantages for movement in the water. Phelps has many characteristics commonly attributed to Marfan Syndrome. Marfan Syndrom is a connective tissue disorder that strengthens the body’s structures and could possibly explain how Phelps swims faster than any other human being. Researchers are also currently studying the gene which codes for slow-twitch muscle fibers that are advantageous for endurance sports. By identifying these genetically inherited advantages could radically change athletic competition, allowing athletes to create specific training regiments beneficial to their unique genetic composition.

Photo Credit: Wikimedia Commons

So research tells us that both beat induction (musical rhythm)  and athletic prowess can be inherited, but the question is how crucial are these inherited traits to success in a given field? What other factors like environment, mentality, mental endurance, or determination play into the molding of a virtuoso or olympian? What really makes a superstar a superstar?

 

For more:

http://www.wired.com/wiredscience/2009/01/babybeats/

http://www.wired.com/wiredscience/2008/08/jamaican-sprint/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%253A+wiredscience+%2528Blog+-+Wired+Science%2529

http://www.wired.com/wiredscience/2008/12/a-gene-test-of/

http://sports.yahoo.com/top/news?slug=ycn-10259115

http://www.genetic-future.com/2008/08/gene-for-jamaican-sprinting-success-no.html

http://www.sciencedaily.com/releases/2011/07/110718121555.htm

Class Fox?

 

Photo Credit: Flickr user- Arudhio

As a kid visiting a zoo did you ever wonder what it would be like to pet the tigers?  Well as you know wild animals are dangerous and they aren’t meant to be tamed, patted or touched… or are they?  According to new studies domestication may not be a learned trait or a trait only found in our dogs, cats, birds and livestock, but a gene that can be bred into wild animals through selective breeding.

In Russia dating back to Stalin’s rule scientists began to wonder if they could breed domestication into a population of animals.   They decided to run their experiment, despite the risk of death because of the government’s aversion to studies on genetics, and started out by heading to fur farms and selecting the calmest foxes who showed the least amount of aggression toward humans.  They began to breed these friendlier foxes and with each generation they began to get friendlier and friendlier foxes to breed.  Today the foxes react to people much like a dog would; they start jumping at the front of their crates and wining for attention and will leap into your arms at the first chance they get.  In fact these foxes even resist going back into their cages because they hate to leave human attention that they love so much.

So how do we know that it’s genetic rather than behavior changes in these foxes?  The scientists thought of this and they kept a control population, for this population they continually bred the most aggressive foxes and got highly aggressive animals that hated human presence.  To test out their theory that this was in fact genetic these scientists took one of the pups bred to be aggressive and gave it to one of the friendly mothers, despite being raised by a mother that loved people this fox remained aggressive to people, as it was bred to do.

Another reason that they are confident that this is genetic is that the foxes physical appearance began to change, they started to look more puppy like for longer, their ears stayed floppy longer, they developed white specs on their coats and their tails curled, all of these traits are typically seen as traits that humans like and that would make the foxes more dog like and more appealing to people.

It may seem hard to believe that a wild animal can be tamed simply through breeding but the reporter of the original article fell so in love with these foxes she now has two sharing her home with her, and her golden retriever.  The scientists and now working to get permits that would allow them to sell some of the friendly foxes as pets (to help fund their research), which leads to the question if we are given the chance to buy them would you ever own a Pet Fox?

 

 

Are Canadians Genetically Superior?

Photo by Anirudh Koul Flickr

I mean they do have Ryan Reynolds,  Rachel McAdams, Ryan Gosling, Ellen Paige, that tall guy from Glee, and Beiber. Well, maybe Bieber doesn’t isn’t a testiment to Canadian superiority, but recent studies have found certain signs of rapid genetic changes among the recent residents of a small Canadian town,  Ile aux Coudres, in the last 140 years. These changes include the average age of first maternity dropping from 26 to 22, resulting in larger families which are advantageous in rural areas.

Now while some may argue that this is merely an effect of the rural culture, anthropologist and geneticist, Emmanuel Milot says “Culture shapes the selection pressures acting on the age at first birth and the reproductive history of women in this population [therefore,] the cultural context was favoring the selection of some genes.” With the help of the Catholic Church’s detailed record keeping, Milot and his team were able to identify this trend as one attributed to genetic rather than environmental changes.

This study supports the school of thought that humans are still evolving and examines microevolution over the course of just a few generations.  Other studies show that certain human populations in different regions are evolving differently still today. A classic example of this regional evolution is the Mongoloid Race‘s decreased amount of sweat glands and small eyes. These are regional adaptations meant to be advantageous against the cold, snowy environment in which they live. Less sweat glands means more water conserved and less sweat released in order to avoid having it freeze on their skin, thus avoiding dehydration and hypothermia. Smaller eyes are beneficial because they help keep the sun’s glare from the snow at a minimum. These are all examples of ancient regional evolutions, similar to the current day changes occurring in some small Canadian villages.

It is definitely exciting to think that we are still evolving and adapting to our environment. It is a testament to the human race’s ability to change and adapt which has led us as far as we are today. Have you noticed any recent changes in your region’s population? Do you see any growing genetic trends in today’s youth?

 

For More:

http://www.wired.com/wiredscience/2009/03/genetic-signatures-of-recent-human-evolution-continued/

http://news.softpedia.com/news/9-Things-You-Did-not-Know-About-Chinese-and-Mongoloid-Race-66420.shtml

http://www.wired.com/wiredscience/2011/10/recent-human-evolution/

http://www.human-evol.cam.ac.uk/Members/Lahr/pubs/YPA-98-41.pdf

Page 4 of 4

Powered by WordPress & Theme by Anders Norén

Skip to toolbar