BioQuakes

AP Biology class blog for discussing current research in Biology

Tag: Genome (Page 2 of 2)

Does long-term endurance training impact muscle epigenetics?

800px-Nucleosome_1KX5_2

 

Epigenetics translates to “above” or “on top of” genetics. To be more specific, Epigenetics is the study of how modification of gene expression can cause changes in many organisms.

A new study from Karolinska Institutet in Sweden explores the theory that long-term endurance training alters the epigenetic pattern in the human skeletal muscle. The team that conducted the research also explored strong links between these altered epigenetic patterns and the activity in genes controlling improved metabolism and inflammation.

The study was conducted using 23 young and healthy men and women. The men and woman would perform one-legged cycling – where the untrained leg would be the control of the experiment. Four times a week and over the course of three months, the volunteers would participate in a 45 minute training session. Though skeletal muscle biopsies, supervisors would measure their markers for skeletal muscle metabolism, methylation status of 480,000 sites in the genome, and activity of over 20,000 genes.

At the end of the study, the researchers concluded that there was a strong relationship between epigenetic methylation and the change in activity of 4000 genes in total. Epigenetic methylation is defined as the “addition of a methyl group to a substrate or the substitution of an atom or group by a methyl group. ” Moreover, it was determined that methylation levels increased when involved in skeletal muscle adaptation and the metabolism of carbohydrates. However, methylation levels decreased in regions associated to inflammation.

Furthermore, Carl Johan Sundberg found that “endurance training in a coordinated fashion affects thousands of DNA methylation sites and genes associated to improvement in muscle function and health.” He believes that this determination could be vital to understanding the treatment of diabetes and cardiovascular disease as well as how to properly maintain good muscle function throughout life.

This article relates very much to our work in class as we learn the Molecular Genetics Unit. It connects because we are learning what happens when mutations occur in one’s genome and the impacts those mutations have on someone. For example, cancer is one of the most researched and explored topics in regard to how modification of gene expression alters organisms. Oncogenes and Tumor suppressor genes have vital impacts on cellular division, changes to cellular function, and the growth of tumors.

Bacteria become ‘genomic tape recorders’, recording chemical exposures in their DNA

EscherichiaColi_NIAID

MIT Engineers have developed a way to create genomic tape recorders out of the Bacteria E. Coli. Timothy Lu, an engineering professor at the university describes the method by which they altered the bacterial DNA in order to allow it to store information. The researchers engineered the cells to produce a recombinase enzyme which can insert a certain sequence of Nucleotides into the genome. However, the trait is useful because the enzyme is activated by specific stimuli. In order to retrieve the information the researchers can either sequence the genome and look for the specific code or look for the trait expressed by the targeted gene by using antibiotics. This process will be useful in the future because of its ability to store long term biological memory. Also, this process transcends previous limitations of genome storage as it is now able to indiscriminately store data as opposed to previous methods that were only able to identify a specific stimulus.

Article Link:

http://www.sciencedaily.com/releases/2014/11/141113142006.htm

Useful Links:

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

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

Image Link:

http://commons.wikimedia.org/wiki/File:EscherichiaColi_NIAID.jpg

Is it Really in Your Genes?

Over and over again, we have been told that our personality traits, our idiosyncrasies, our weaknesses, and our merits are all because of our genome.  Supposedly, if someone studies our DNA, they will know exactly the type of person we are, but is that really true?  According to new research, it’s not.  Researchers have discovered that is extremely common for a person to have mosaicism, or multiple genomes.  In other words, chimeras make up a higher fraction of people than scientists originally thought.  Some have many variations, or mutations, in certain parts of the body, and some people even have genomes that are from other people.  People can acquire a different set of genes along with their original genes as early as in the womb.  Previously, there were just hints about the idea of multiple genomes, but the hints have turned into definite statements.  The evidence of multiple genomes is changing the way scientists think. Links between rare diseases and multiple genomes are becoming apparent.  After figuring this out, scientists are figuring out links between more common disorders and genome multiplicity.  Although many forms of cancer and other diseases are linked to mosaicism, most instances of multiple genomes are benign.  It is also changing the way that forensic scientists view DNA evidence in crime investigations.  The biggest change of all is perhaps that scientists now have to consider that DNA from a finger prick may not be the same DNA in a muscle cell or brain cell.  This means that scientists can’t tell what is happening in all the organs just from a simple blood test or test from one organ.  They can’t be certain of what is happening in other parts of the body.  However, scientists are hard at work discovering more powerful ways to investigate our multiple genomes.

http://commons.wikimedia.org/wiki/File:Genome.jpg

http://commons.wikimedia.org/wiki/File:Genome.jpg

HeLa Cells Sequenced!

Photo By: University of Arkansas
Wellcome Trust

The immortal cell, also known as HeLa cells, have been used by scientists for years for various medical research. But, until today the genome of HeLa cells was never known. Jonathan Landry and Paul Pyl, from the European Molecular Biology Laboratory in Heidelberg, performed the study to sequence Henrietta Lacks‘ genome, and what they found was quite remarkable. They found striking differences between her cells and the cells of a normal human being. The genome had abnormalities in both chromosome number and structure. They also found that countless regions of the chromosomes in each cell were arranged in the wrong order and had extra or fewer copies of genes, all telltale signs of chromosome shattering. Chromosome shattering has recently been found to be linked to 2-3% of cancers. Seeing as how Henrietta Lacks’ cells were taken from a cervical tumor, this is not a surprising find. However, because her genome had never been sequenced this was all new to Landry and Pyl. They said, “The results provide the first detailed sequence of a HeLa genome. It demonstrates how genetically complex HeLa is compared to normal human tissue. Yet, possibly because of this complexity, no one had systematically sequenced the genome, until now.” Another scientist, Lars Steinmetz, who led the project, added, “Our study underscores the importance of accounting for the abnormal characteristics of HeLa cells in experimental design and analysis, and has the potential to refine the use of HeLa cells as a model of human biology.” Although this study is nowhere near groundbreaking, it still helps to highlight the importance of the extensive differences that cell lines can have from their human references.

For more information on this study and HeLa cells in general, you can go to:http://www.science20.com/news_articles/genome_hela_cell_line_sequenced-106181

 

GATTACA review

Who ever knew a movie staring Jude Law, Uma Therman and Ethan Hawke does not just explore romance and drama but also takes a look into the revolutionizing and weary scientific future our world has yet to see!  The movie, GATTACA(standing for the 4 DNA bases-Guanine, Adenine, Thymine, Thymine, Adenine, Cytosine, Adenine), starts with the birth of Vincent Freeman, an ordinary child just like you and me.  But unfortunately for him, Vincent falls way below average in his society that revolves around eugenics.

I belonged to a new underclass, no longer determined by social status or the color of your skin. No, we now have discrimination down to a science. –Vincent Freeman in GATTACA

This discrimination that Vincent is referring to is based on ones genetic profile.  In the GATTACA world, the creation of a child occurs in a lab, where there parents can choose what genes they want and don’t want their child to inherit, making for one, almost genetically perfect kid.  In the movie, they have facilities that resemble bank tellers but are in fact genetic “profilers”.  One can bring a strand of hair they found to the facility and receive a print out of that persons genetic profile, along with it stating if that person is Valid(genetically engineered) or invalid(ordinarily created).  Because Vincent was not created this way he is forever categorized as In-valid, causing him to have limited options in life, like not getting hired.

I don’t want to give away more of the story, but it goes into deep investigation of what this world, that potentially can one day happen, would be like.  It questions the morality and ethics behind genetic modification, profiling and discrimination.  It also shows a very depressed world devoid of joy.

In today’s world, we already have genome services similar to the ones in GATTACA. The company 23andMe can create your genetic profile with a swab of your DNA.  You can find out what your genetic ancestry is life, what disease you are at risk for, why you like the foods you like and so on.  Some people are very hesitant to viewing their genetic profile. after reading this article, of a women who had her genetic profile made through 23andMe, do you think you would want yours made?  Why or why not?

License: http://creativecommons.org/licenses/by/2.0/deed.en
Link to Photo: http://www.flickr.com/photos/wonderferret/2854706889/
Photographer: wonderferret

Genome Project Helps Connect Ethnicity to Diseases

Though people from all over the globe share over 99% of the same DNA, there are subtle differences that make us all individuals

Scientists at the Washington University School of Medicine in St. Louis have started the “1,000 Genomes Project” in which they will decode the genomes of 1,000 people from all over the world in hopes of finding genetic roots of both rare and common diseases worldwide. On October 31st, the results of DNA variations on people from 14 different ethnic groups were published, but the scientists hope for the project to expand to involve 2,500 people from 26 different world populations. According to Doctor Elaine Mardis, co-director of the Genome Institution at Washington University, “[scientists] estimate that each person carries up to several hundred rare DNA variants that could potentially contribute to disease. Now, scientists can investigate how detrimental particular rare variants are in different ethnic groups.”

 

We are One

Everyone on earth share 99% of the same DNA. That means you, your best friend, your mortal enemy, your boyfriend/girlfriend, next door neighbor, and The President of the United States all share 99% of your DNA. However, there are rare variants that occur with a frequency of less than 1% in a population that are thought to contribute to both rare diseases and common conditions (i.e cancer, diabetes). The rare variants explain why some medications do not effect certain people or cause nasty side effects (i.e insomnia, vomiting, and even death).

 

The goal of the “1,000 Genomes Project” is to identify rare variants across different populations. In the pilot phase of the program, researchers found that most rare variants different from one population to another, and the current study supports this theory.

 

The Study

Researches tested genomes from populations from the Han Chinese in Beijing (and the Southern Han Chinese in China) to Utah Residents with ancestry from Europe to the Toscani people of Italy to the Colombians in Columbia. Participants submitted an anonymous DNA sample and agreed to have their genetic material on an online database. Researchers than sequenced the entire genome of each individual in the study five times. However, decoding the entire genome only detects common DNA changes. In order to find the rare variants, researchers sequences small portions of the genomes about 80 times to look for single letter changes in the DNA called Single Nucleotide Polymorphisms, or SNPs.

 

The Results and Importance

The Study concluded that rare variants vary from one population to another. Researchers found a total of 38 million SNPs, including 99% of the rare variants in the participants’ DNA. In addition, researchers found 1.4 million small sections of insertions or deletions and 14,000 large sections of DNA deletion. The “1,000 Genomes Project” is incredibly important in medical science. It now allows researchers to study diseases, such as cancer, in specific ethnic groups. I personally think this project in incredibly important. As an Ashkenazi Jew from Eastern Europe, my family has a medical history of certain cancers and diseases. With the results of the “1,000 Genome Project,” researches could potentially find out why, and maybe even find a cure for some of these diseases.

Page 2 of 2

Powered by WordPress & Theme by Anders Norén

Skip to toolbar