Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Gene Therapy Presentation

SCED 370 Big Issue Project

on 21 August 2013

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Gene Therapy Presentation

Gene Therapy: A Controversial Issue
Science of gene therapy
Obstacles in Gene Therapy
polygenic disorders = caused by many genes
more common, but more complex and difficult to cure
monogenic disorders = caused by a single gene
easier to cure, but more rare
more difficult to isolate causal gene
less funding for research
Gene therapy...
is the alteration of human DNA to alleviate conditions caused by missing, damaged, or malfunctioning genes
could potentially cure deadly diseases such as cystic fibrosis, immunodeficiency disorders, cancer, and many more
currently an experimental treatment, still in development

How do genetic disorders happen?
the human body needs proteins to function normally and stay healthy
cells manufacture those proteins
cells need genes (sections of DNA) to tell them how to make proteins
genes can mutate
harmful mutations =
not enough proteins
too many proteins
abnormal proteins
abnormal cell functioning = genetic disorders such as...
cystic fibrosis
Duchenne's muscular dystrophy
Type 1 diabetes
congenital blindness
immunodeficiency disorders
sickle cell anemia
Lou Gherig's disease
neurological disorders (Huntingtons, Parkinsons, etc.)
and many more
2 Types of Gene Therapy
Somatic cell
targets only the genes in a patient's body cells, so only the individual who receives the therapy is affected
targets the genes in a patient's eggs or sperm, so changes can be passed on to offspring
not in development
Goals of Gene Therapy
cure genetic disorders by
repairing abnormal genes
replacing abnormal genes with normal ones
adding normal genes to a patient's genome
cure cancer by
inactivating cancer-causing genes
delivering genes to cancer cells that will cause them to 'commit suicide', prevent them from spreading, or make them more susceptible to anti-cancer drugs
provide genes to body cells to enhance immune response to cancer cells
cure other diseases by improving human cells' immune response to viruses and bacteria
Gene Therapy Process
delivery mechanisms called 'vectors'
as vectors, most trials use viruses whose own DNA or RNA has been inactivated and replaced by human DNA segments containing normal versions of abnormal genes

plasmids can also be used as vectors
circular DNA molecules
used by bacteria to transfer genes to other bacteria
safer than viral vectors
(a.k.a. in vivo)
(a.k.a. ex vivo)
several different types of viruses can serve as vectors and vary in their ability to accept genes, deliver them to cells, and what type of cells they tend to infect

polygenic vs. monogenic dilemma
immune response to viral vectors
the human body's natural reaction to viruses, even inactivated ones containing human DNA, can be deadly for humans
Jesse Gelsinger, 1999
errors in gene delivery
new genes can end up where they aren't supposed to, in the wrong cells or in the wrong location on a cell's chromosomes, and interfere with other genes' normal function, causing more problems
children cured of SCID by gene therapy developed leukemia, 2001
Opposition to gene therapy
We should cease research and development in gene therapy altogether because...
It's risky
risk to patients (dying, suffering, developing worse complications)
risk to descendants (germ-line gene therapy)
risk to others (fear that viral vectors could reactivate and spread disease)
It could have far-reaching and detrimental future implications for society
designer babies
'gene doping'
unnecessary genetic enhancements
increased social stratification
if too expensive only wealthy would benefit
decreased genetic diversity

Support for gene therapy
Gene therapy is a relatively new field of medicine, so reasonable setbacks and sacrifices should be expected
We should continue research and development in this area because...
there have been some successes
our technology and knowledge still has a lot of room for improvement
the potential to end so much human suffering and learn more about how life works justifies continuance

Subjects of gene therapy
people suffering from severely debilitating disorders with absolutely no other treatment options
lab animals, especially mice
also frogs, worms, flies, yeast
Implications for education
NGSS recommends introducing genetic concepts including inheritance and variation of traits at the middle school level
MS-LS3 Heredity: Inheritance and Variation of Traits
students can... “Develop and use a model to describe why structural changes to genes (mutations) located on chromosomes may affect proteins and may result in harmful, beneficial, or neutral effects to the structure and function of the organism “
NGSS also provides standards at the high school level related to genetics, requiring students to go into even greater depth.
Gene therapy would be a great contextual issue through which to teach these concepts because
it is current and cutting-edge science
it could cure many well-known disorders
it is controversial - giving students a chance to consider ethical issues and exercise developing opinions
understanding gene therapy requires understanding of the concepts being taught
Discussion Questions
If you had a genetic disorder, would you volunteer for a gene therapy trial even if it was very risky? Why or why not?
If you could improve your IQ, athletic abilities, or change your appearance through gene therapy, would you do it? Why or why not?
If you had an abnormal gene that could be passed on to your children and cause them problems, but a certain type of gene therapy could fix that gene and make it so your children wouldn't have it, would you want that gene therapy to be available to you? What if the therapy could have unforeseen consequences for your descendants?
Images (in order of appearance)

Scientific Journal Articles
• Aiuti, A., et al. (2009). Gene therapy for immunodeficiency due to adenosine deaminase deficiency. New England Journal of Medicine, 360(5), 447-458. Retrieved from http://www.nejm.org/doi/pdf/10.1056/NEJMoa0805817
• Buchen, L. (2009). Brain disease treated by gene therapy.Nature, Retrieved from http://www.nature.com/news/2009/091105/full/news.2009.1067.html
• Callaway, E. (2011). Gene therapy offers hope for parkinson's disease. Nature, Retrieved from http://www.nature.com/news/2011/110317/full/news.2011.167.html
• Chial, H. (2008) Rare genetic disorders: Learning about genetic disease through gene mapping, SNPs, and microarray data. Nature Education 1(1)
• Dalgleish, A. (1997). Editorial - why: gene therapy?. Gene Therapy, (4), 629-630. Retrieved from http://www.nature.com/gt/journal/v4/n7/pdf/3300488a.pdf
• Hacein-Bey-Abina, S., et al. (2003). A serious adverse event after successful gene therapy for x-linked severe combined immunodeficiency (letter to the editor).New England Journal of Medicine, 348(3), 255-256. Retrieved from http://www.nejm.org/doi/pdf/10.1056/NEJM200301163480314
• Hunt, S. (2008) Controversies in treatment approaches: Gene therapy, IVF, stem cells, and pharmacogenomics. Nature Education 1(1)
• Mendell, J., et al. (2010). Dystrophin immunity in duchenne's muscular dystropy. New England Journal of Medicine, 363(15), 1429-1437. Retrieved from http://www.nejm.org/doi/pdf/10.1056/NEJMoa1000228
• Nathwani, A., et al. (2011). Adenovirus-associated virus vector–mediated gene transfer in hemophilia b. New England Journal of Medicine, 365(25), 2357-2365. Retrieved from http://www.nejm.org/doi/pdf/10.1056/NEJMoa1108046
Other Sources
• National Cancer Institute, NIH (2006, August 31). Gene therapy for cancer: Questions and answers. Retrieved from http://www.cancer.gov/cancertopics/factsheet/Therapy/gene
• US National Library of Medicine. (2013, July 29). How does gene therapy work?. Retrieved from http://ghr.nlm.nih.gov/handbook/therapy/procedures
• US National Library of Medicine. (2013, July 29). What is gene therapy?. Retrieved from http://ghr.nlm.nih.gov/handbook/therapy/genetherapy
• Barlow-Stewart, K. Centre for Genetics Education, (2013).Gene therapy fact sheet 27. Retrieved from website: http://www.genetics.edu.au/Publications and Resources/Genetics-Fact-Sheets/GeneTherapyFS27
• Bianchi, Z. (2013, March 25). The current status of gene therapy. Retrieved from http://suite101.com/article/the-current-status-of-gene-therapy-a192095
• Walters, L. US Department of Energy, Office of Science. (1999). "ethical issues in human gene therapy". Retrieved from Human Genome Program website: http://web.ornl.gov/sci/techresources/Human_Genome/publicat/hgn/v10n1/16walter.shtml
• Wilson, J. US Department of Energy, Office of Science. (1999). "human gene therapy: Present and future". Retrieved from Human Genome Program website: http://web.ornl.gov/sci/techresources/Human_Genome/publicat/hgn/v10n1/15wilson.shtml
Full transcript