Falsifying DNA- questioning the Gold Standard

August 21, 2009

Earlier this week, a group of scientists in Israel shook the world of forensic sciences and questioned the use of DNA testing as the “gold standard”.  In a paper published by the Forensic Science International: Genetics journal, researchers showed that it is possible to fabricate DNA evidence. In this paper, the scientists fabricated saliva and blood samples that contained DNA from a person other than the donor of that blood and saliva!  Also, the researchers showed that through the use of a DNA database, they could utilize a profile within that database and construct a sample of DNA to match that profile without needing any tissue from that person.  In the world of science, this makes a lot of sense, as many people use synthetic DNA oligos in almost every molecular laboratory!

Thankfully, Dr. Frumkin who is the lead author on the paper, has developed a test to distinguish real DNA samples from fake ones using epigenetic modifications, specifically DNA methylation.  In the human genome, 70% of the DNA is methylated, meaning that it contains methyl group modifications in a CpG dinucleotide context. Methylation at the promoter region is associated with gene silencing.  Synthetic DNA, however, would lack this specific epigenetic modification, and therefore can be distinguished from the real deal.

As our world becomes increasingly reliant on scientific technologies, the idea that DNA can be planted at a crime scene is very scary.  Hopefully with tests like the one generated by Dr. Frumkin will be common practice to ensure that science stays ahead of the game.

By Alisha Jamal, University of Toronto


Removal of the stem cell ban—what does it all mean for Science?

August 15, 2009

Earlier this year, U.S. President Obama lifted the restriction of federal funding of human embryonic stem cells—a controversial field of biomedical research. The ban, originally introduced by President Bush on August 9, 2001 in an effort to stop the destruction of embryos, banned scientists from making new embryonic stem cell lines, but allowed them to use the 21 lines already created. The band was frustrating for many scientists who argued that that the pre-existing lines were not diverse enough to study many diseases.   New stem cell lines, which may have disease-specific mutations, would have also allowed scientists to investigate a greater range of disease pathways. These new lines could yield fundamental insight into how diseases are caused and how they may be treated or cured. Further, many of the established lines were defective which could make them dangerous to transplant into people. Although laboratories still continued to use stem cells to study diseases, they had to find their own ways to fund their projects and often had to design separate lab areas.

Stem cells, which are derived from the inner cell mass of a developing blastocyst, are pluripotent, meaning they can differentiate into any cell of the three germ layers: endoderm, mesoderm and ectoderm. Scientists believe that stem cells hold the “key” for discovering why diseases occur, and will provide treatments for Alzheimer’s, Parkinson’s, diabetes and heart disease to name a few.

Opponents of the ban however, argue that stem cells are not even needed anymore to generate pluripotent cells since scientific advances have shown promise for the ability to induce adult cells to go back to the pluripotent state. These cells, known as induced pluripotent stem cells or iPS have recently begun to show a lot of promise. For example, one of our own, Dr. Andras Nagy, a Toronto researcher based out of Mount Sinai was the first to reprogram adult human cells into embryonic-like stem cells without using viruses that could potentially cause cancer. In a seminal Nature paper, Nagy’s group describes a new PiggyBac transposition system where they can insert the reprogramming factors and subsequently take them out. This discovery will change the face of stem cell therapies because in essence, we will be able to take a person’s own cell, reprogram it, lead it to differentiate into a necessary cell type, and put it back into them.

In any case, the field of pluripotent cells is a “hot” area of research with promise for advancing human health. With Obama overturning the ban, stem cell research will likely continue to advance with newly developed strong collaborations and likely the development of stem cell databases. This will hopefully get us one step closer to finding the cause, and perhaps the cure, for many diseases that affect human health.

By Alisha Jamal, University of Toronto


H1N1…Should we worry?

May 12, 2009

The Public Health Agency of Canada has released the following info on H1N1 Flu (also know as the “Human Swine Flu”):

H1N1 Flu Virus (Human Swine Flu) has been reported in Canada, Mexico, the United States and other countries around the world.  Swine influenza is a strain of the influenza virus that usually affects pigs, but which may also make people sick.  It is not, however, transmitted by eating pork.  H1N1 Flu Virus (Human Swine Flu) is a respiratory illness that causes symptoms similar to those of the regular human seasonal flu.  The symptoms include fever, fatigue, lack of appetite, coughing and sore throat.  Some people with H1N1 Flu Virus have also reported vomiting and diarrhea.  The virus is contagious and the recommendations to avoid infection are the same as for regular seasonal influenza – frequent handwashing, getting an annual flu shot, covering coughs and sneezes, and staying home when ill.

It is too soon to call this a Pandemic.  We should note that influenza pandemics vary from mild, moderate to severe.  Although, antiviral medications are available, such as Tamiflu (Oseltamavir) and Relenza (Zanamavir), these medications are restricted for moderate to severe cases of the Swine Flu.  Current vaccinations for the Human Influenza virus are not likely effective against swine flu, but vaccines will be developed against the swine flu if pandemic status should arise.  Most cases in Canada and the US have been mild as compared to the cases in Mexico.  So far there has been one death linked to the flu in Canada and four people hospitalized, while the majority of cases have been mild.  

As of today (Monday, May 11, 2009), the total of confirmed A/H1N1 flu cases in Canada rose to 330, with 46 new cases added during the day.  The province of Ontario confirmed 34 new cases since Saturday, bringing the total number of cases in the province to 110, the most among all provinces.  All of the new cases are mild.  Fifty-six of the 110 cases are males and 54 females.  Other new cases were reported by Alberta, Saskatchewan, Quebec and Nova Scotia. 

We would like to hear your thoughts on H1N1.  Please email your opinions to submit@cslsr.ca for the chance to be featured in the next CSLSR quarterly newsletter.


Sleep…Please!!!

April 5, 2009

During the course of evolution, humans have evolved internal physiological and behavioural mechanisms that are closely linked to the time in their environment. It is believed that pairing an organism’s behaviour and physiological reactions to their environment increases their chance of surviving by ensuring that they are active at times of the day that are beneficial to them. Modern society, however, has thrown our evolutionary adaptation out of balance. Our present society requires that a portion of the population is awake at all times of the day. Power generating facilities need employees to monitor electricity generation, doctors and emergency workers must be available and factory workers ensure that a maximum level of production is reached. Nevertheless, living in a 24 hour society has consequences, especially for shift workers. Apart from higher rates of accidents, shift workers are prone to suffer from a variety of health problems including: sleep disorders, gastrointestinal disorders, cardiovascular health problems, lipid intolerance and a higher risk of developing diabetes.

This leads us to the following questions: why are shift workers more prone to health problems than non-shift workers? Can these workers simply make up the sleep they have lost at night during the day? The answer lies within a phenomenon known as circadian rhythms. Circadian rhythms are the daily variations in physiology and behaviour that occur within every organism. Circadian rhythms are maintained by a master biological clock, known as the suprachiasmatic nucleus (SCN). The periodicity of the clock is determined genetically and reflects the natural wake/sleep cycle. Circadian rhythms therefore require that behavioural and physiological phases in the body are aligned to obtain proper sleep. Sleeping at times when the phases of the circadian cycle are not aligned (for example, when body temperature is rising and melatonin levels are falling) will result in poor sleep quality. As such, shift workers who are attempting to sleep during the day after a night of work may have difficulty sleeping due to the fact that the phases of their circadian rhythm are no longer synchronized. Circadian rhythms can adjust over time, but the process is lengthy and workers may have been assigned to a different work shift by the time their circadian rhythm re-synchronizes. In addition, light and exercise can shift circadian rhythms, and hence, it may be difficult for workers to sleep well if they are exposed to light (even dim light) during the day.

In itself, poor sleep or sleep deprivation can have dire consequences. Lack of sleep often results in errors, slower reaction times, decreased vigilance, impaired memory and reduced motivation. Results for task performance after 17-19 hours of sustained wakefulness are similar to those obtained with individuals who have a blood alcohol level of 0.05%. 20-25 hours of sustained wakefulness will produce similar results to those obtained with individuals with a blood alcohol level of 0.1%. This is above the legal limit for alcohol. The maximum amount of hours that a hospital intern is allowed to work is currently 24 hours. This is nonetheless dangerous considering the effects of sleep deprivation following such a long work period. Sleep deprivation has been linked to many documented medical errors.  Although controls have been established to regulate hours of work, present legislation often fails to recognize the effects of sleep deprivation on mental alterness and performance. Perhaps it is time to review our current regulations to ensure that our workers are safe.   

The information for this article was obtained from:

Rajaratnam, Shantha MW, J. Arendt. 2001. Health in a 24-h society. Lancet. 358: 999-1005

 


The Health Council of Canada Wants You To Speak Up!

March 4, 2009

Health care in Canada accounts for 40% of provincial budgets, $172 billion was spent last year nationwide. While the economy continues to slump into recession, it’s time to examine how funding is being allocated, and how to make our money worker harder and more efficiently.

The Health Council of Canada is asking Canadians to voice their opinions by visiting www.canadavalueshealth.ca. The website is an interactive forum, which allows visitors the chance to debate issues, post their views and engage with others.

Everyone is encouraged to participate – feedback will be presented to the public and government officials. This is an excellent opportunity to be heard! The CSLSR is hopeful our membership will get involved and emphasize the importance of research grants.

The ultimate vision of the CSLSR is to bring student researchers together at the undergraduate, graduate, professional and post-graduate levels. This will create an opportunity for academics and clinician-scientists to exchange information and knowledge,with the aspiration of transforming clinical theories and research into practical applications.

Each year CSLSR members are given the unique opportunity to present their research at our annual conference. Without research grants from various government organizations, this opportunity might not be available. Collaborative research between academics and scientists is fundamental to the improvement and advancement of Canada’s health care system.

On behalf of the CSLSR we urge you to get online and share your thoughts – together let’s keep research at the forefront of Canada’s health care budget!

We want to hear from you too! Please check out the site (www.cslsr.ca) and send us your comments/discussion points to post on our blog.


February 19, 2009

The concept of health can be seen from two different perspectives. Health was originally defined as state in which there is an absence of disease or infirmity. In 1948, however, the World Health Organization (WHO) moved away from this definition to include psychological and social factors. The WHO currently defines health as “a state of complete physical, mental and social well-being, and not merely the absence of disease or infirmity”. Although this perspective of health attempts to include variables that may impact the health status of an individual, it represents a challenge for clinicians and researchers who aim to construct instruments measures to monitor the results of medical interventions. The challenges stem from difficulties in defining “well-being”. As such, many measures still focus on the absence of disease or infirmity.

The WHO’s modification of what constitutes health has translated into greater attempts to measures quality of life—this has specifically resulted in the creation of the fields of health outcome research and health technology assessment. Appropriate health outcome measures are crucial for the creation of an evidence-based body of knowledge and the implementation of best-practice guidelines. They serve to monitor the efficacy of treatments as well as the cost-effectiveness and the net-benefits of interventions. Nonetheless, these measures must respect the patient’s perspective. Clinicians and researchers must remember that patients tend to place different values on health states than physicians and other clinician groups. There is therefore a need for outcome measures that respect the perspective of patients as well as other stakeholders such as clinicians and researchers. Measures will only be respected if they adhere to the perspective of key stakeholders, such as the ones of physicians and researchers, in the process. This will likely raise the question of how these stakeholders value outcomes that are deemed necessary by patients, and hence, who will bear the responsibility to decide which measures to incorporate in the evaluation. To this day, the search for adequate measures produces highly contested debates….but the future looks promising.

– by Nath


Submit Current Research Opinions

February 18, 2009

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