February 28, 2009

Stem cells: Human Trial for Spinal Cord Injuries

Geron Corporation just got permission from the FDA to start human clinical trials of a new medication based on human embryonic stem cells. This will be the first clinical trial of a stem cell based therapy in humans. The new therapy is designed to treat acute spinal cord injuries, and hopes to restore function to the damaged tissues. Translation, to make people who are currently paralyzed walk again.

Medical researchers are praising adult stem cells and their more committed kin, progenitor cells, for their ability to produce different types of specialized cells. The potential of using these cells to repair or replace damaged tissue holds great promise for cancer therapies and regenerative medicine.
However, the question that must first be answered is what determines the ultimate fate of a stem or progenitor cell? According to an article from the Berkeley Laboratory, a team of researchers led by Mark LaBarge and Mina Bissell, appear to be well on the road to finding out. Working with unique microenvironment microarrays (MEArrays) of their own creation, LaBarge, Bissell, and their collaborators, a cell and molecular biologists in Berkeley Lab's Life Sciences Division, have shown that the ultimate fate of a stem or progenitor cell in a woman's breast – whether the cell develops normally or whether it turns cancerous – may depend upon signals from multiple microenvironments.
Previous studies on how microenvironments affect the development of adult human stem or progenitor cells have been based on the behaviour of these cells in culture (in vitro) where they are exposed to a single molecular agent. However, when these cells are in an actual human being (in vivo) they are surrounded by a multitude of other cells plus a supporting network of fibrous and globular proteins called the extracellular matrix (ECM), as well as many other nearby molecules, all of which may be simultaneously sending them instructional signals.
The GRNOPC1 Clinical Program
Patients eligible for the Phase I trial must have documented evidence of functionally complete spinal cord injury with a neurological level of T3 to T10 spinal segments and agree to have GRNOPC1 injected into the lesion sites between seven and 14 days after injury. Geron has selected up to seven U.S. medical centers as candidates to participate in this study and in planned protocol extensions. The sites will be identified as they come online and are ready to enroll subjects into the study.

Although the primary endpoint of the trial is safety, the protocol includes secondary endpoints to assess efficacy, such as improved neuromuscular control or sensation in the trunk or lower extremities. Once safety in this patient population has been established and the FDA reviews clinical data in conjunction with additional data from ongoing animal studies, Geron plans to seek FDA approval to extend the study to increase the dose of GRNOPC1, enroll subjects with complete cervical injuries and expand the trial to include patients with severe incomplete (ASIA grade B or C) injuries to enable access to the therapy for as broad a population of severe spinal cord-injured patients as is medically appropriate.

February 22, 2009

Genomic Research: the next step!

What are the next step forward?

Discovering the sequence of the human genome was only the first step in understanding how the instructions coded in DNA lead to a functioning human being.

The next stage of genomic research will begin to derive meaningful knowledge from the DNA sequence. Research studies that build on the work of the Human Genome Project are under way worldwide.

The objectives of continued genomic research include the following:
  1. Determine the function of genes and the elements that regulate genes throughout the genome.
  2. Find variations in the DNA sequence among people and determine their significance. The most common type of genetic variation is known as a single nucleotide polymorphism or SNP (pronounced “snip”). These small differences may help predict a person’s risk of particular diseases and response to certain medications.
  3. Discover the 3-dimensional structures of proteins and identify their functions.
  4. Explore how DNA and proteins interact with one another and with the environment to create complex living systems.
  5. Develop and apply genome-based strategies for the early detection, diagnosis, and treatment of disease.
  6. Sequence the genomes of other organisms, such as the rat, cow, and chimpanzee, in order to compare similar genes between species.
  7. Develop new technologies to study genes and DNA on a large scale and store genomic data efficiently.
  8. Continue to explore the ethical, legal, and social issues raised by genomic research.

Stem Cells: the basic 2

Pros and Cons of Embryonic and Adult Stem Cells

There are significant medical and scientific differences between embryonic and adult stem cell research and therapy. Here is a comparison between the two types, including some of the advantages and disadvantages of each.

Embryonic Stem Cell Advantages
1. Flexible, appear to have the potential to make any cell
2. Immortal, one ES cell line can potentially provide an endless supply of cells with defined characteristics
3. Availability, embryos from in vitro fertilization clinics
Embryonic Stem Cell Disadvantages
1. Difficult to differentiate uniformly and homogeneously into a target tissue
2. Immunogenic, ES cells from a random embryo donor are likely to be rejected after transplantation
3. Tumorigenic, capable of forming tumors or promoting tumor formation
4. Destructive, destruction of developing human life
Adult Stem Cell Advantages
1. Flexibility, special adult-type stem cells from bone marrow and from umbilical cord have been isolated recently which appear to be as flexible as the embryonic type
2. Inducibility, already somewhat specialized, inducement may be simpler
3. Not immunogenic, recipients who receive the products of their own stem cells will not experience immune rejection
4. Availability, Relative ease of procurement, some adult stem cells are easy to harvest (skin, muscle, marrow, fat), while others may be more difficult to obtain (brain stem cells). Umbilical and placental stem cells are likely to be readily available
5. Non-tumorigenic, tend not to form tumors
6. No harm done to the donor
Adult Stem Cell Disadvantages
1. Limited quantity, can sometimes be difficult to obtain in large numbers
2. Finite, may not live as long as ES cells in culture
3. Less flexible (with the exception of #1 above), may be more difficult to reprogram to form other tissue types
Adult stem cells are a “natural” solution. They naturally exist in our bodies, and they provide a natural repair mechanism for many tissues of our bodies. They belong in the microenvironment of an adult body, while embryonic stem cells belong in the microenvironment of the early embryo, not in an adult body, where they tend to cause tumors and immune system reactions. Most importantly, adult stem cells have already been successfully used in human therapies for many years. As of this moment, NO therapies in humans have ever been successfully carried out using embryonic stem cells. New therapies using adult type stem cells, on the other hand, are being developed all the time. Here are but a few of the many examples of success stories using adult stem cells.
Cancers: Brain Cancer , Retinoblastoma, Ovarian Cancer , Skin Cancer: Merkel Cell Carcinoma, Testicular Cancer, Tumors abdominal organs Lymphoma, Non-Hodgkin’s lymphoma, Hodgkin’s Disease, Acute Lymphoblastic Leukemia, Acute Myelogenous Leukemia, Chronic Myelogenous Leukemia, Juvenile Myelomonocytic Leukemia, Chronic Myelomonocytic Leukemia, Angioimmunoblastic Lymphadenopathy , Multiple Myeloma, Myelodysplasia, Breast Cancer, Neuroblastoma, Renal Cell Carcinoma, Sarcoma, Ewing’s Sarcoma, Waldenstrom’s macroglobulinemia, Hemophagocytic lymphohistiocytosis. POEMS syndrome, Myelofibrosis. Auto-Immune Diseases: Diabetes Type I (Juvenile), SLE, Sjogren’s Syndrome, Myasthenia, Autoimmune Thrombocytopenia, Scleromyxedema, Scleroderma, Crohn’s Disease, Behcet’s Disease, Rheumatoid Arthritis, Juvenile Arthritis, Multiple Sclerosis, Idiopatic Polychondritis, Systemic Vasculitis, Alopecia Universalis, Buerger’s Disease. Cardiovascular: Acute Heart Damage, Chronic Coronary Artery Disease. Ocular: Corneal regeneration. Immunodeficiencies: Severe Combined Immunodeficiency Syndrome SCID, X-linked Lymphoproliferative Syndrome, X-linked Hyper-immunoglobulin M Syndrome. Neural Degenerative Diseases and Injuries: Parkinson’s Disease, Spinal Cord Injury, Stroke Damage. Anemias and Other Blood Conditions: Sickle Cell Anemia, Sideroblastic Anemia, Aplastic Anemia, Red Cell Aplasia, Amegakaryocytic Thrombocytopenia, Thalassemia, Primary Amyloidosis, Diamond Blackfan Anemia, Fanconi’s Anemia, Chronic Epstein-Barr Infection. Wounds and Injuries: Limb Gangrene, Surface Wound Healing, Jawbone Replacement, Skull Bone Repair. Other Metabolic Disorders: Hurler’s Syndrome, Osteogenesis Imperfecta, Krabbe’s Leukodystrophy, Osteopetrosis, Cerebral X-Linked Adrenoleukodystrophy. Liver Disease: Chronic Liver Failure, Liver Cirrhosis. Bladder Disease: End-Stage Bladder Disease.

February 16, 2009

Stem Cells: the basic

Today I begin a short discussion about Stem Cells. How you know, this is a very actual and controversial theme with many implication in medicine. We will start with some definitions and general principles. Of course, this is a special paper for a blog and it will be incomplete but not superficial due that every day we have new information in this field. I hope enjoy these short essays.

FACT 1: What are pluripotent stem cells?
The stem cells are cells capable of sustaining unlimited division cycles indefinitely perpetuating the same original style but with ability to differentiate, become a stem or trunk, and become one of the 200 specialized cell varieties and cease its divisions. They are the normal reservoir of new cells that are necessary to replace damaged or dead. Retain the capacity to multiply as such to be required, which will culminate in its differentiation of cells in tissue repair. Serving as a sort of repair system for the body, they can theoretically divide without limit to replenish other cells as long as the person or animal is still alive. When a stem cell divides, each new cell has the potential to either remain a stem cell or become another type of cell with a more specialized function, such as a muscle cell, a red blood cell, or a brain cell. Stem cells have two important characteristics that distinguish them from other types of cells.
First, they are unspecialized cells that renew themselves for long periods through cell division. The second is that under certain physiologic or experimental conditions, they can be induced to become specialized cells with special functions such as the beating cells of the heart muscle or the insulin producing cells of the pancreas. Scientists are trying to understand two fundamental properties of stem cells that relate to their long term self-renewal: a) why can embryonic stem cells proliferate for a year or more in the laboratory without differentiating, but most adult stem cells cannot; and b) what are the factors in living organisms that normally regulate stem cell proliferation and self-renewal.

FACT 2: Origin of stem cells
Scientists primarily work with two kinds of stem cells from animals and humans: embryonic stem cells and adult stem cells, which have different functions and characteristics. They discovered ways to obtain or derive stem cells from early mouse embryos more than 20 years ago. Many years of detailed study of the biology of mouse stem cells led to the discovery. In 1998, they isolated stem cells from human embryos and grow the cells in the laboratory. These were called human embryonic stem cells. The embryos used in these studies were created for infertility purposes through in vitro fertilization procedures and when they were no longer needed for that purpose, they were donated for research with the informed consent of the donor. Stem cells are important for living organisms for many reasons. In the 3- to 5-day-old embryo, called a blastocyst, stem cells in developing tissues give rise to the multiple specialized cell types that make up the heart, lung, skin, and other tissues. In some adult tissues, such as bone marrow, muscle, and brain, discrete populations of adult stem cells generate replacements for cells that are lost through normal wear and tear, injury, or disease.
Adult stem cells are now call adult progenitor stem cells. Those who lack a population of stem cells/progenitor throughout life will not be able to self-repair. Not even explain the reason why some bodies and others have no such cell populations. The tissues are deficient in them, mainly the brain, heart, spinal cord, eye and kidney. They have an important role in the regeneration process would be fired induced by implanted stem cells, in which case it opens another line: the search for the factors that trigger or induce such a response in quality and/or greater than the usual amount to disease or tissue damage.
Much has been speculated about the type of cell in which you can become a progenitor mononuclear cell in adult stage, if only give rise to another cell or tissue from which most of any other tissue from the same embryological layer. One example is the renovation or replacement of spare cells in the blood. Bleeding or donation to stimulate stem cells in bone marrow cells needed to create, passing several stages of differentiation, followed by separation of such stem cells. The difference between stem cells and bone marrow that are differentiating into blood cells is the loss of their ability to divide, which can be done during certain stages, but not in others. The cells do not fully mature but directed toward a specific type of differentiation, called precursors or progenitors, rather than stem cells, accepting that the subtle difference between them is not always so clear.
See: Culture of Mouse Neural Stem Cell Precursors

FACT 3: Stem cells from fetal tissues
At approximately 12 weeks of gestation primitive bodies are formed and their final location. Over the next 6 months, they have increased in size and develop the ability to operate independently of the placenta. As the fetus grows very quickly, all the tissues and organs, including brain contains stem cells, which aroused the interest of researchers and society concerned about the possible tampering with them. From three sources: trophoblast, primitive germ cells and fetal tissues.
As with many other cell types, the trophoblast cells can auto perpetuate and scientist were unable to prevent their differentiation. It seems to be happening with all the stem cells, at least in laboratory cultures, continually divide and differentiate, suggesting that such differentiation is the process that occurs by default, which means a natural limit to the size of organs and a barrier to tumor formation. If so, the environment that supports such a state of lack of differentiation, should express the genes whose products inhibit.
In tissues, in addition, the medium must also inhibit cell division unless new cells are needed. An essential contribution was made by Janet Rossant in Toronto, to find that the fibroblast growth factor 4 (FGF4) using heparin as a co-factor was as necessary as the layers of fibroblasts nutrients to keep in trophoblast undifferentiated stem cells. The injection of these cells in the blastocyst produced only trophoblastic tissue. Other stem cells that aroused great interest are the embryonic or fetal-fetal cells. Researchers have to get parental approval for donations of fetal tissues between 5 and 12 weeks of gestation, according to the legislation in most of the countries where the harvesting of them is authorized and regulated. The window of 5-12 weeks is advantageous because until the 5th week almost all cells are stem cells with almost no degree of differentiation and high mitotic rate that can generate Teratomas. From 12 weeks, the immune system HLA (Human Antigen Leukocyte) is already developed and the implantation of stem cells can cause immune rejection in the receiver.

FACT 4: Embryonic stem cells.
Before organogenesis, the embryo of any species is a compressed collection of cells with the potential to become any organ or tissue, which are called pluripotent. First described in mice in the laboratory is relentless and infinitely divided and maintain the ability to differentiate into any cell type when exposed to the proper growth factor, such as the formation of nerves can transmit electrical and chemical signals, similar to the body. Here comes the enthusiasm to develop regenerative therapies in Parkinson, Alzheimer, spinal injuries and degenerative diseases of retina. They are undoubtedly the most pluripotent of all, have the greatest therapeutic potential. They are immortal and capable of pluripotent differentiationl. Chromosomal composition remains stable over many cell cycles. Jobs in USA, Australia and Israel are giving rise to cells of the three embryonic layers. Them were injected into immune suppressed mice and they originated Teratomas with intestinal epithelial cells (endoderm), striated and smooth muscle (mesoderm) and squamous epithelium (ectoderm).
See: Propagation of Embryonic Stem Cells

FACT 5: Stem cells by parthenogenesis.
This process so far only achieved in primates and an experimental basis. This is the artificial activation of an egg without having been fertilized by changes in flow of calcium. The cell line had the same feature from other embryonic stem cells: normal chromosomes, capable of endless cycles of growth and division, contain significant amounts of telomerase, which is thought to play a fundamental role in the maintenance of the integrity of chromosomes through successive divisions and had allegedly antigens associated with embryonic stem cells. They can become any other race, including dopaminergic neurons. Their pluripotent action has been demonstrated by the appearance of teratomas appropriate models of rats, where the 3 layers of tissue were found: blood vessels, intestines primitive smooth and striated muscle, bone and cartilage. These results suggest that although the eggs activated by this process not give rise to an individual, can theoretically provide pluripotent cells. Many questions and problems with this line have not yet been overcome.
See: Derivation of Human Embryonic Stem Cells by Immunosurgery

FACT 6: Stem cells by nuclear transplantation
Since every cell in the body contains all the chromosomes, each cell of every tissue is a reservoir of all the genes of each individual. The only exception is the mature sperm, which contains only half, with populations of sperm X or Y. It was found that nuclear material (chromosomes) of a cell implanted into an egg may be home to an individual identical to the donor of nuclear material. This is called cloning, Greek clon, or branch line that once planted can cause the same plant. This type of cloning could be used to create stem cells in need of individual, with their own genetic and replacing damaged or lost. The gene replacement therapy could help millions of diabetics, a hemophilic, and so on. Today, it is subject to restrictions for fear that human cloning arouses in some social and religious groups.


FACT 7: How a cell becomes in another?
The mechanisms of action are:
1. Cell differentiation: the process to become a mature cell, not divisible, which specializes in the expression of gene products required to meet tissue specific functions, such as the synthesis of specific proteins from cells also specialize in secretion and driving.
2. Trans-differentiation or plasticity: Conversion of a differentiated cell to another, with or without prior cell division.
3. Metaplasia: Conversion of a cell or tissue type into another.

Trans-differetiation also includes the conversion between undifferentiated stem cells from different tissues. Cell divisions are usually involved but sometimes not, as evidenced by the lack of uptake of 5-BrdU during processing. While there is little evidence of that, has proved attractive to assume that stem cells from a particular tissue in the body like those in its embryonic state. I used to assume that these stem cells are predetermined to form cell types that just tissue, but is not that simple. Several studies have postulated that the stem cells are so complex as to have plastic behavior depending on the environment in which they are highly sensitive to signals emanating from damaged tissues. The transplantation of bone marrow cells was the first demonstration of a cell type that can cause another. It was found the formation of muscle from bone marrow harvested from transgenic mice in which the promoter 3F of myosin light chain was used to guide the expression of nuclear beta-galactosidase. They took bone marrow of this strain and is injected into immunosuppressed mice to whom myonecrosis caused by chemical cardiotoxin. In bone marrow there is no expression of beta-galactosidase but was activated in cells that became associated with the muscle of the host. Although trans-diffrentiation happened, it was much slower (months) caused by the resident satellite cells, which became in muscle in a period of days. This time difference indicates that metaplasia from muscle to bone marrow could be a multi-step process that involves migration, differentiation and possibly final determination. Other researchers also differentiated tissues derived from cells of bone marrow.

FACT 8: Clinical and therapeutic uses
Research on stem cells is advancing knowledge about how an organism develops from a single cell and how healthy cells replace damaged cells in adult organisms. This promising area of science is also leading scientists to investigate the possibility of cell-based therapies to treat disease, which is often referred to as regenerative or reparative medicine. Stem cells are one of the most fascinating areas of biology today. But like many expanding fields of scientific inquiry, research on stem cells raises scientific questions as rapidly as it generates new discoveries.
Countless diseases and functional deficiencies seem likely to be treated with stem cells. Diabetes, liver cirrhosis, arthritis, neurological diseases (Alzheimer, Parkinson), spinal cord injuries, ischemic or idiopathic dilated cardiomyopathies, acute myocardial infarction, anemia, leukemia, finally, have been treated with this method and others (kidney failure, some types of cancer, etc..) are currently being studied. Obviously there is a tendency to get a cell lineage with enough potential to regenerate tissues needed, stored and available for immediate use. We will discuss these issues in detail further.

Where can I get more information?
For a more detailed discussion of stem cells, see the following Web sites:
http://www.news.wisc.edu/packages/stemcells/ The University of Wisconsin's Web site about stem cells, written for general audiences.
http://www.eurekalert.org/ EurekAlert! is a publicly accessible science news site run by the American Association for the Advancement of Sciences. Search for "stem cells."
http://scitechdaily.com/ A site that offers a range of news articles, features, and commentaries about science and technology topics. Search for "stem cells."
http://www.sciam.com/ The Web site for Scientific American. Search for "stem cells."
http://www.reuters.com/newsChannel.jhtml?type=scienceNews The Reuters news site for stories about science. Search for "stem cells" and select "News and Pictures."
http://www.stemcellresearchnews.com/ A commercial, online newsletter that features stories about stem cells of all types.

February 7, 2009

The Athlete's gene: ACTN3

Every year in the Olimpic Games more and more marks are broken for awesome athletes. Every day we read at the newspapers how much money earned an elite’s athlete. That is the image that our children see like an inspiration for their future lives and some parents use these fantasies to force their children to follow the hard live of a professional sportiest. Whatever motivation always we search to way to increase our capacities and newly genetics play a fundamental role with the ACTN 3 gene.

ACTN3 actinin, alpha 3 [Homo sapiens] Alpha-actinin is an actin-binding protein with multiple roles in different cell types; it is located in chromosome 11q13.1.
The ACTN3 gene encodes the protein α-actinin-3. α-Actinin-3 is an actin-binding protein that is structurally related to dystrophin. Alpha-actinin is a cytoskeletal actin-binding protein and a member of the spectrin superfamily, which comprises spectrin, dystrophin and their homologues and isoforms. It forms an anti-parallel rod-shaped dimer with one actin-binding domain at each end of the rod and bundles actin filaments in multiple cell-type and cytoskeleton frameworks. In non-muscle cells, alpha-actinin is found along the actin filaments and in adhesion sites. In striated, cardiac and smooth muscle cells, it is localized at the Z-disk and analogous dense bodies, where it forms a lattice-like structure and stabilizes the muscle contractile apparatus. Besides binding to actin filaments alpha-actinin associates with a number of cytoskeletal and signaling molecules, cytoplasmic domains of transmembrane receptors and ion channels, rendering it important structural and regulatory roles in cytoskeleton organization and muscle contraction.
In humans, two genes encode for skeletal muscle α -actinins: ACTN2, which is expressed in all skeletal muscle fibers, vs. ACTN3, whose expression is limited to fast-twitch muscle fibers (100% of type IIb/x fibers and 50% of type IIa fibers). α-Actinins are important structural components of the Z-membrane where they form the crosslink between the thin actin filaments. They have a static function in maintaining ordered myofibrillar arrays and a regulatory function in coordinating myofiber contraction).
Alpha-actinins are structural proteins of the Z-line. Human skeletal muscle expresses two alpha-actinin isoforms, alpha-actinin-2 and alpha-actinin-3, encoded by their respective genes ACTN2 and ACTN3. ACTN2 is expressed in all muscle fiber types while only type II fibers, and particularly the type IIb fibers, express ACTN3.
ACTN3 (R577X) polymorphism results in loss of alpha-actinin-3 and has been suggested to influence skeletal muscle function. The X-allele is less common in elite sprint and power athletes, than in the general population, and has been suggested to be detrimental for performance requiring high power.
α-Actinins interact with themselves, structural proteins of the contractile machinery, metabolic enzymes, and signaling proteins, among them are also members of the Z-line localized calsarcin family. These bind to calcineurin, a Ca2+- and calmodulin-dependent protein phosphatase, which is a signaling protein and is hypothesized to play a role in the determination of muscle fiber type and muscle hypertrophy, although it does not seem to be implicated in muscle fiber growth in regenerating muscle.
Based on genetic epidemiological studies, about half of the variability in fiber type distribution in human muscles is determined by genetic factors. Through its interaction with calcineurin, polymorphisms in the ACTN3 gene could conceivably contribute to heritability of fiber type distribution. The force-generating capacity of type II muscle fibers at high velocity, the speed of movements, and the capacity to adapt to training are all strongly genetically influenced. The contribution of genetic factors in strength measures in part varies according to the angle, to the contraction type, and to some extent the contraction velocity. Contractile property differences according to the presence/absence of α-actinin-3 in sarcomeres of fast-type muscle fibers might also contribute to individual differences in power output.

A common variant of the ACTN3 gene, R577X, results in complete deficiency of the alpha-actinin-3 protein in the fast skeletal muscle fibers of more than a billion humans worldwide. Scientific studies involving elite level athletes suggest that the presence of this specific muscle protein contributes to the muscle's ability to generate forceful contractions at high velocity. Depending on ethnicity, 20 to 50 per cent of people have a variant of the gene R577X, which prevents the ACTN3 gene from producing the muscle protein. Generally, African-Americans have the lowest incidence of the mutation, while Asians have the highest.

This gene is one measure of natural-born athletic ability. Other studies have shown that athletes having the variant in both copies of the ACTN3 gene may have a natural predisposition for endurance, such as distance running, distance swimming and cross-country skiing. Athletes having the variant in one copy of their ACTN3 gene may be equally suited for sports requiring both endurance and sprint / power characteristics such as basketball, tennis, volleyball and cycling.
Athletes that do not carry this variant in either copy of the ACTN3 gene may have a natural predisposition for speed / power sports such as football, weight lifting and sprint events.

The alpha-actinins are an ancient family of actin-binding proteins that play structural and regulatory roles in cytoskeletal organisation and muscle contraction. Alpha-actinin-3 is the most-highly specialised of the four mammalian alpha-actinins, with its expression restricted largely to fast glycolytic fibres in skeletal muscle. Intriguingly, a significant proportion (approximately 18%) of the human population is totally deficient in alpha-actinin-3 due to homozygosity for a premature stop codon polymorphism (R577X) in the ACTN3 gene. Recent works have revealed a strong association between R577X genotype and performance in a variety of athletic endeavours. Several authors are currently exploring the function and evolutionary history of the ACTN3 gene and other alpha-actinin family members. The alpha-actinin family provides a fascinating case study in molecular evolution, illustrating phenomena such as functional redundancy in duplicate genes, the evolution of protein function, and the action of natural selection during recent human evolution. On the other hand, knowing this information may be helpful, not in eliminating choices for sport activities but adding exposure to a host of team or individual sport events that may come easier to a young athlete.

Well, this is the landscape. What do you think? I guess that we need to make the next reflections:

  1. What happens if you have the mutation and you really wish to be an athlete? This is not a real limitation, the success in the sports depend of several variables like training, support, desire, effort, money and it needs to add a very important random factor like the good luck.
  2. What about if you don’t have any mutation? Are you a complete athlete? Well, no. It’s clear that all will depend of the same factors that I showed before.
  3. Is this a necessary genetic test? No, like all the genetic test is up to you. Even if you are young and want to decide about your choices in your future, is this a test only for fun for now. If you are a veteran professional sportiest believe you don’t want to know anything about your genetic condition.
  4. What about the future? It will be very interesting, probably we’ll see more specific test in this field related to specific sports.

It remains a lot of aspects to discuss in this theme. The following is a list of ACTN3 gene research articles that likely are interesting for you:
  1. North K. (2008) Why is alpha-actinin-3 deficiency so common in the general population? The evolution of athletic performance. Twin Research in Human Genetics. 11:384-394.
  2. Druzhevskaya et al. (2008) Association of the ACTN3 R577X polymorphism with power athlete status in Russians, European Journal of Applied Physiology 103:631–634
  3. Roth et al. (2008) The ACTN3 R577X nonsense allele is under-represented in elite-level strength athletes. European Journal of Human Genetics 16:391-394
  4. Yang et al. (2003) ACTN3 Genotype Is Associated with Human Elite Athletic Performance. American Journal of Human Genetics 73:627-631
  5. MacArthur and North (2004) A gene for speed? The evolution and function of alpha-actinin-3. BioEssays 26:786-795

On the news: Video Journal

Awasome Journal: JoVE


Journal of Visualized Experiments (JoVE) is a video journal for biological research that have the next categories: Medicine, Neuroscience, Development Biology. Cellular Biology, Plant Biology, Microbiology, Immunology, Basic Protocols.

The Journal of Visualized Experiments (JoVE) was established as a new tool in life science publication and communication, with participation of scientists from leading research institutions. JoVE takes advantage of video technology to capture and transmit the multiple facets and intricacies of life science research. Visualization greatly facilitates the understanding and efficient reproduction of both basic and complex experimental techniques, thereby addressing two of the biggest challenges faced by today’s life science research community: i) low transparency and poor reproducibility of biological experiments and ii) time and labor-intensive nature of learning new experimental techniques.

The complexity and breadth of life science research has increased exponentially in recent years. Research progress and the translation of findings from the bench to clinical therapies relies on the rapid transfer of knowledge both within the research community and the general public. Written word and static picture-based traditional print journals are no longer sufficient to accurately transmit the intricacies of modern research.

As every researcher in the life sciences knows, it can take weeks or even months to learn, perfect, and apply new experimental techniques. It is especially difficult to reproduce newly published studies describing the advanced state-of-the-art techniques. Thus, much time in the laboratory is spent learning techniques and procedures. This is a never ending process for experimental scientists as methodologies in this fast-growing field evolve and change with each coming year (e.g. genomics and proteomics, most dramatically). The time and resource-consuming process of learning and staying current with techniques and procedures is a rate-limiting step in the advancement of scientific research and drug discovery.

JoVE opens a new frontier in scientific publication by promoting efficiency and performance of life science research. Visualization of the temporal component, or the change over time integral to many life science experiments, can now be done. JoVE allows you to publish experiments in all their dimensions, overcoming the inherent limitations of traditional, static print journals, thereby adding an entirely new parameter to the communication of experimental data and research results.

You can see a very interesting experiments like:

Medicine: Human In-Vivo Bioassay for the Tissue-Specific Measurement of Nociceptive and Inflammatory Mediators, Stanford University School of Medicine


Psychology: Functional Imaging with Reinforcement, Eyetracking, and Physiological Monitoring, Columbia University


Neuroscience: Preparation and Maintenance of Dorsal Root Ganglia Neurons in Compartmented Cultures, Harvard Medical School.

Do you want to try?