3.5 Genetic modification and biotechnology

Assessing risks associated with scientific research—scientists attempt to assess the risks associated with genetically modified crops or livestock.

Genetically Modified Organisms is a great topic to encourage deeper thinking and to have students consider the impacts of science on society. There is a lot of genuine mistrust and concern with this, but there is also a lot of misinformation and misunderstanding of the science, so it makes a good topic to link to the importance of scientific literacy.

I like to use the different thinking routines created by Project Zero for Visible Thinking and have written about them before when discussing stem cells. For GMOs, we used the Circle of Viewpoints to try to understand the many perspectives on this topic.

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Circle of Viewpoints – Visible Thinking

We came up with a great range of viewpoints:

  • A concerned parent/consumer
  • An FDA spokesperson
  • A worker at Monsanto
  • A large-scale commercial farmer in the US
  • A small-scale organic farmer in the US
  • A subsistence farmer in Cambodia
  • A Greenpeace activist
  • A UN worker
  • the Pope
  • an ecologist
  • a member of the Just Label It coalition

It was a really useful exercise and the students tried to get under the skin of their characters! It helped the students identify the range of viewpoints and we were able to narrow down to some of the key concerns about the technology. To guide our discussion we focused principally on three examples of GMOs: Bt Cotton, Golden Rice and the recently approved AquaAdvantage GM Salmon. The risks we discussed included: possible health concerns/allergies; the risk of genetic contamination of wild organisms; increasing the evolution of Bt resistant pests and risks to non-target species. The role-play allowed us to balance these risks with the possible increases in yield and efficiency, nutritional benefits and less use of pesticides. The issues of labelling and the possible (emotional?) response we have to knowing that the food is GMO could provide the basis for a good TOK lesson as well. We also discussed the extensive testing that the GM salmon has been forced to undergo and that it has been nearly 20 years of research and development – at what point should we accept that something is low-risk? When do we decide that we have sufficient evidence in the natural sciences to support a conclusion?

The main challenge we found was placing a time limit on the discussion, as we could comfortably have debated this for several more lessons.

 

“Circle Of Viewpoints | Project Zero”. Pz.harvard.edu. N. p., 2016. Web. 15 Aug. 2016.

Best Holiday Read 2016

Like all good biology teachers, I try to load up my summer reading list with the latest science books.  One book in particular stands out this year and I think it deserves its own blog post!  Described as a “biography of the gene”, The Gene by Siddhartha Mukherjee is a phenomenal book.  Beautifully written (the author, a cancer physician and researcher, has a genuine literary touch) it is a fascinating overview of our understanding of the gene.  It takes us from the first Aristotelian musings on inheritance all the way forward to today’s latest insights into genetics and molecular biology.  All the famous geneticists from the Nature of Science are in here: Mendel, Darwin, Morgan , Watson, Crick, Franklin, Sanger and too many more to list.  In fact, the book is the perfect compendium for IB Biology students!  The narrative is lively and engaging and the individual personalities of the scientists leap off the page. It is worth making time for, even in the busy schedule of an IB student.

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11.4 Reproduction (HL)

Assessing risks and benefits associated with scientific research—the risks to human male fertility were not adequately assessed before steroids related to progesterone and estrogen were released into the environment as a result of the use of the female contraceptive pill.

There are a lot of myths surrounding the environmental effects of the contraceptive pill, despite the fact that it is one of the most widely-taken and best studied drugs in use. According to the ARHP, more than 13 million American women use the pill and there is over 50 years of data on its safety and effectiveness (Moore et al.).

Concerns have been raised that the additional estrogen, largely a synthetic estrogen called Ethinyl Estradiol, being released into the environment through usage of the pill has resulted in elevated rates of these hormones in drinking water.  As steroid hormones, these are known as Endocrine Disruptive Chemicals (EDCs) – chemicals that could alter the hormonal balance and control of organism’ physiology (Moore et. al.) Clearly then, there are legitimate concerns for the health impacts of any chemical that can disrupt an animal (or person’s) endocrine system.  The increase in male infertility as well as the recorded feminisation of some species of fish over this time period has amplified this issue. But is the contraceptive pill a significant part of this problem?

A comprehensive review (Wise et al.) examined this statement and found that the contraceptive pill is a negligible cause of any synthetic estrogens in waterways. It does highlight the role of agriculture and industry as sources of EDCs; for example, it points out that the amount of synthetic estrogen given to livestock in the US is five times greater than that consumed by all the women on the pill (Wise et. al.)

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Sources of endocrine-disrupting compounds in the water supply (Moore et al.)

Returning to the statement in the Nature of Science, there remains the issue of whether the risks were properly considered before the widespread use of these drugs and thus whether a full ethical review was conducted.  However, the link between estrogen compounds in the environment and the pill seem tenuous at best and it is other sources of steroid-based hormones that need to be addressed.

Sources:

Moore, K. et al. Birth Control Hormones In Water: Separating Myth From Fact. arhp.org. 2011. Web. Mar 30, 2016.

Wise A, O’Brien K, Woodruff T. Critical review: are oral contraceptives a significant contributor to the estrogenicity of drinking water?. Environ Sci Tech. 2011;1:51–60

A.5 Neuropharmacology

Assessing risks associated with scientific research—patient advocates will often press for the speeding up of drug approval processes, encouraging more tolerance of risk.

Another NOS with great links to TOK (though this might be too late in the course for some G12 students!) Testing experimental drugs on humans is incredibly important for the development of new drugs but it does raise several ethical concerns.  One is the tension that exists between the need to rigorously ensure that the drug is effective and safe (which can take years) and the needs of patients requiring treatment.  This can be especially acute if patients have terminal or incurable conditions and they are desperate for a possible cure.

In the US, the Food and Drug Administration (FDA) has the responsibility to review and approve drugs for use.  There are four pathways for faster approval, shown in the graphic below:

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Pathways to faster approval of drugs (FDA)

 A recent example of this dilemma was the Ebola outbreak in West Africa in 2014-15.  There were minimal supplies of an experimental drug called ZMapp and it was perceived to have helped the recovery of two American aid workers.  However, the drug was still in the experimental stages and doctors did not know if the drug really helped the Americans or if there were other factors involved.  In the case of an emerging epidemic where there are few medical treatments available, it can be tempting to fast-track any drug in development.  But the risks of unknown, harmful side-effects cannot be ignored and this places public health officials in a difficult situation.  What might be your approach using the different schools of ethical thought here? How does reason and emotion influence your opinion of this?

“Fast Track, Breakthrough Therapy, Accelerated Approval, Priority Review”. Fda.gov. N. p., 2016. Web. 15 Mar. 2016.

Pollack, Andrew. “Ebola Drug Could Save A Few Lives. But Whose?”. Nytimes.com. N. p., 2014. Web. 15 Mar. 2016.

2.8 Respiration and Ethics

Assessing the ethics of scientific research: the use of invertebrates in respirometers has ethical implications.

The use of animal models in biological experiments has a long history. Indeed, many of our most important discoveries were made possible by using animal test subjects. However, using animals at any time during an experiment has ethical implications that need to be evaluated.

Any scientific research involving animals will have to satisfy an ethics board as to the justification for using and/or experimenting on animals. Two key issues that scientists have to consider might include: what suffering or pain will the animal experience and are there alternatives to using animals?  There is a process in the UK called the 3R’s – replacement, refinement and reduction of the use of animals in research (Festing, S. and Wilkinson, R.).  This process, while acknowledging that animals may be required in certain circumstances, aims to ultimately reduce these to only the most essential experiments.

There is often a difference in concern between invertebrates and vertebrates in terms of what ethical rules apply to them.  Most people probably care less about the fate of cockroaches or crickets in a respirometer experiment than about the use of mammals in medical research.  However, it is still important to evaluate the ethical use of invertebrates in the same way as vertebrates. In addition to the issues of pain/suffering and replacement, we should consider:

  • whether the animals can be released back into their natural habitat
  • whether it is ethical to remove them in the first pace
  • whether we can minimise any pain or suffering that may take place in the experiment.

The IBO has published a document on the use of animals in experiments and it is very clear that any animal (invertebrate or not) must be treated ethically and must not be subject to any suffering or environment outside its normal range. This link from the Nuffield Foundation outlines an experiment based on this; take note of their ethical issues paragraph after the methods.

Sources:

Allott, Andrew, and David Mindorff. Biology. Oxford: Oxford University Press, 2014. Print.

Festing, Simon, and Robin Wilkinson. The Ethics Of Animal Research. Talking Point On The Use Of Animals In Scientific Research. EMBO Reports 8.6. 2007: 526-530. Web. 27 Jan. 2016.

 

6.5 Neurons and synapses

Cooperation and collaboration between groups of scientists—biologists are contributing to research into memory and learning. (4.3)

As we learn in TOK, the image of the lone scientist coming up with brilliant, individual insights is generally false; science is a discipline where collaboration and cooperation are critical to developing new scientific knowledge. This is particularly true today, as disciplines become ever more specialised.

There are innumerable examples of this taking place in memory studies, as the interaction between neurons, the brain and other aspects of physiology and biochemistry mean that researchers from many different disciplines are needed.

One recent example is a study investigating the role of hormones (specifically estrogen) on learning and cognition (Phan et al.).  Adding the hormone to female mouse brains seemed to boost short-term learning; the team concluded that it helps induce the formation of immature synapses (which occurs during development) and that this provides the foundation for developing and then storing new memories.

A look at the author affiliations shows the importance of collaboration:

  • Department of Psychology, University of Guelph, ON, Canada
  • Neuroscience Program, University of Guelph, Guelph, ON, Canada
  • Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada
  • Laboratory of Neurobiology and Behavior, The Rockefeller University, New York, NY 10065

Such examples can be found with any search of the current scientific literature, highlighting that scientists must work together not just in studies of learning and memory, but in all fields.

Source

Phan, Anna et al. “Rapid Increases In Immature Synapses Parallel Estrogen-Induced Hippocampal Learning Enhancements”. Proceedings of the National Academy of Sciences (2015): 201522150. Web. 16 Dec. 2015.

University of Guelph. “Tie between estrogen, memory explored by researchers.” ScienceDaily. ScienceDaily, 15 December 2015.

11.1 Antibody production and vaccination

Consider ethical implications of research—Jenner tested his vaccine for smallpox on a child.

The story of Edward Jenner is a fascinating one and he played a key early role in the development of vaccines. The PBS Series “Rx for Survival” has a nice little dramatisation on his vaccine research in Episode 1: Disease Warriors (9m 13s – 12m 01s), though the whole episode is worth watching.

Jenner had noticed that milk-maids contracted cow pox, a non-fatal disease from cows, in the course of their work.  While this might make them ill for a time, they rarely ever caught the much more dangerous relative of cow pox, small pox. To test his theory, he inoculated a farm boy with pus from a milk-maid’s cow-pox pustules; the boy was unwell for a few days but made a full recovery. Jenner then exposed him to live small pox virus and he survived.

The ethical issues seem clear, but on reflection may not be so cut-and-dried.  Under modern medical standards, it is considered unethical to expose patients to live, virulent strains of a pathogen in order to test the efficacy of a vaccine. Such experiments would also not be done on children as young as eight. It is also likely that Jenner never received informed consent for the experiment as well.

However, there is a good case to be made that Jenner was merely following the ethical standards of the day, and that in fact, inoculation of this sort was relatively common in rural England (Abc). Given the very real danger of contracting the fatal small pox, it might be argued that the possibility of protection from the disease was sufficient motivation.  We can also link to TOK here and think about the challenges of applying modern ethical standards to past events, particularly where the context is so very different to today.  This link is a very nice ethical discussion of this, including a hypothetical hearing before an ethics review board (Davies).

It was not without controversy at the time, however, with the anti-vaccination movement already forming its arguments.  The famous cartoon below shows their misplaced fears:

The_cow_pock
The Cow Pock – 1802 (Wilson and Marcuse)

Sources

Abc. Ockham’s Razor: Defending Edward Jenner, 2015. Web. 15 Dec. 2015.

Bioethicscourse.info,. “Jenner On Trial: Introduction”. N. p., 2015. Web. 15 Dec. 2015.

Davies, H. “Ethical Reflections On Edward Jenner’s Experimental Treatment”. Journal of Medical Ethics 33.3 (2007): 174-176. Web. 15 Dec. 2015.

Wilson, Christopher B., and Edgar K. Marcuse. “Vaccine Safety–Vaccine Benefits:Science And The Public’s Perception”. Nat Rev Immunol. 1.2 (2001): 160-165. Web. 15 Dec. 2015.

6.3 – Ethics and Penicillin

6.3 Risks associated with scientific research—Florey and Chain’s tests on the safety of penicillin would not be compliant with current protocol on testing.

Study this NOS in conjunction with the Application from 6.3:
Florey and Chain’s experiments to test penicillin on bacterial infections in mice

While Alexander Fleming gets much of the credit for discovering penicillin, it was the work of Florey and Chain during the Second World War that led to its availability as a breakthrough medicine: the two “…transformed penicillin from an interesting observation into a life saver. ” (Torok).   All three shared the Nobel prize in physiology or medicine in 1945 and Florey was knighted and decorated by the US, UK, France and Australia for his role in influencing the outcome of the war.

The NOS refers to the trials Florey and Chain and their team undertook to get penicillin out to the troops as quickly as possible. Florey and Chain began their research in 1939 and were faced with the challenge of extracting enough useful penicillin to be used.  This was compounded by the outbreak of war and the fact that such a medicine could be crucial to the Allies.

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The penicillin mould (Bos)

In 1940, they were ready to test on mice.  Eight were chosen and inoculated with lethal doses of streptococcia.  Four were then given injections of penicillin and four were left as controls. Within 24 hours, the untreated mice were all dead and those that received penicillin survived. This promising result led to an immediate human trial – a policeman suffering from a facial infection caused by a scratch from a rose bush.  The patient responded very favourably to treatment but supplies of penicillin ran out and he relapsed and died.  Successful subsequent human trials on five patients were enough to convince them of its efficacy and production was increased for release to patients and eventually scaled up to provide the Allied troops with the drug.

Consider these points as the start for a discussion on the ethical issues and possible risks involved in these experiments:

  1. The original study sample used only eight mice.
  2. The mice were exposed to lethal doses of infection.
  3. Human trials were begun without enough of the drug.
  4. The drug was released after studies on a sample size of five people.
  5. The potential for alleviating human suffering and curing disease was enormous.

On an ethical side note, Florey did not patent the extraction of penicillin, even though he would have been fabulously wealthy as a result.  The UK government advised him that it should be available for all humankind.  US drug companies however did patent it, with the result that the UK had to pay royalties to them.

Sources

Abc.net.au,. ‘Howard Florey – Maker Of The Miracle Mould’. N. p., 2015. Web. 18 Nov. 2015.

Bos, Carole “Alexander Fleming and Penicillin – “The Wonder Drug”” AwesomeStories.com. May 25, 2015. Nov 18, 2015.

 

5.3 Classification

Cooperation and collaboration between groups of scientists—scientists use the binomial system to identify a species rather than the many different local names.

This is one of my favourite topics (as a former zoologist) and one that lends itself to a number of different activities with students. To emphasise how different languages classify organisms in very different ways, I ask the students to come up to the board and write the name “elephant” (or another readily identifiable animal) in their mother tongue.  Here’s what we come up with today:

How many ways to say elephant?
How many ways to say elephant?

Out of 11 students in the HL class, we had 8 different mother tongues represented in the picture above: Shona, English, German, Khmer, Chinese (Mandarin), Vietnamese, Urdu and Japanese.  This provides a clear indication of the need for a uniform system of classification.  It can also be augmented by a side discussion about, to continue the trend, elephant grass, elephant seal, elephant shrew, etc.

The next part of the lesson allows us to focus on the Khmer language (a good opportunity to link to our host-country). In Khmer, the word for tiger is ខ្លា (Klah)  and the word for sun-bear is ខ្លាឃ្មំ (klah kmoom). We discuss how this intimates a very close relationship between the two species.  But how close?

Binomial classification of the tiger and the sun bear.
Binomial classification of the tiger and the sun bear.

A binomial classification then reveals that the two animals are indeed closely related to the level of the Order, but then separate into different Families, Genus and Species.  This makes it very apparent to the students that scientists can use the binomial system to improve communication and understanding of the classification and relationships between living organisms. Thus both the Nature of Science and the required content are covered in this lesson.  An additional extension could be to name a common name in English and then have students translate it into their mother tongue.  Jellyfish is a good example, as it is nonsensical when translated into many languages (not to mention it is not a fish!)

How do other IB Biology teachers teach classification?  How do others use language to frame the lesson?  I would love to hear from you.

1.1 Cells – an Introduction Part 2.

Ethical implications of research—research involving stem cells is growing in importance and raises ethical issues

A prescribed title essay in TOK recently (May 2014) was about the extent that ethics should limit the production of knowledge in the natural sciences. Stem cells was the natural choice of an example for many students who chose this. This topic is the perfect vehicle to link TOK explicitly into the biology classroom and in doing so, allows for some wonderful discussion about this topic.  This year, we used a modified Tug for Truth as a way of structuring the discussion.

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Tug for Truth is part of the Visible Thinking truth routines from Harvard’s Project Zero.  You can download PDFs for all of the different routines from their website.  The lesson plan for the Tug-for-Truth suggests picking a controversial topic and then “tugging” the truth by mentioning either true or false claims.  In our case, one side tugged in favour of fewer restrictions on stem cell research and the other side called for tighter restrictions.  Each side had to justify their claim, thereby moving the “rope” in their direction.  The stronger or better-reasoned the claim, the greater the tug. Focusing on TOK allowed students to use the Ways of Knowing to frame their claims – emotion was one that was used consistently.

For students, there are a range of great websites available for understanding the stem cell debate and what researchers are discovering: try the University of Utah’s excellent Stem Cells information page, this detailed fact-sheet from Euro Stem Cells  and this summary of research advances from the Genetics Policy Institute.