Personalised medicine for cancer

Introduction Mutations that are occured at oncogenes and tumor suppressor genes causes genomic alteration. These genomic alterations play a key roles to occur formation, progressing and metastasis of cancer. To understand developing and progressing of cancer mechanism and also enhancing personalized cancer treatments are both associated with analyzing and distinguishing of all genomic alteration in … Read more

Therapeutic potential of phages

Amounting to the largest biomass on the planet, bacteriophages are seen to have a huge potential in the biopharmaceutical landscape. With the rapid emergence of antibiotic resistance in bacterial pathogens, research interest in phage therapy has grown. Controlling the lytic action of phages will allow for the development of an inducible phage therapy and will … Read more

The application of genetic engineering to medicine

CHAPTER 1 INTRODUCTION 1.1 WHAT IS GENETIC ENGINEERING? Genetic engineering or genetic modification is the alteration or modification of an organism’s genome using modern DNA technology (Biotechnology). It usually involves the introduction of foreign DNA or synthetic genes into the organism; the new resulting organism is often referred to as transgenic and or genetically modified … Read more

Improving agricultural productivity (focus on Tanzania)

Abstract: Agriculture is the most lucrative factor of Tanzania’s economy. The sector accounts for 26.8% of the GDP, and about 80% of the workforce. However, only a quarter of the 44 million hectares of land in Tanzania is used for agriculture. The biggest aspects of Tanzania’s low agricultural productivity is lack of response to changing … Read more

Embryonic gene editing – should the US change current legislation?

The future of embryonic gene modification continues to present a heavily complicated ethical dilemma for various intellectual individuals. Some believe that it is highly likely one day humans will intentionally modify their babies to fit a certain standard, while others argue that it seems unlikely for this to occur. When discussing whether the United States … Read more

The regulatory regime for CRISPR gene editing is inapplicable and inefficient

The advent of CRISPR/Cas9 genome editing is completely revolutionizing the way we approach scientific problems. This technology provides a relatively simple gene-editing platform to modify entire genomes. Although CRISPR holds great promise in transforming the way we approach human diseases, it remains largely unregulated because of the outdated and restrictive regulatory scheme for biotechnology in … Read more

Will genome editing replace HSCT for blood diseases?

Genome editing involves the modification of the genome at a specific site in a DNA sequence [1]. Today, genetic engineering is used in overcoming many single-gene ailments such as cystic fibrosis, haemophilia, and a plethora of other diseases. However it was not until 2012, that the genome editing technique known as the Clustered Regularly Interspaced … Read more

Genetically engineering a human embryo

Should we do it? Would it make us a ‘better’ species? In a world of advancing technology, we suddenly have the power to edit our DNA like a word processor; we could potentially eliminate the chances of inherited diseases altogether which would ultimately save countless lives. However, this may open a door to creating genetically … Read more

Is cloning “playing God?”

Is cloning “playing God?”  The short answer is yes, but that isn’t necessarily a bad thing.  By creating life and being able to control the characteristics that are expressed in humans and other organisms, a large benefit can be derived. Humans have a knack for identifying problems and tinkering and tailoring until they find just … Read more

About Gene Editing

Background

Genome editing, or gene editing, is a method that allows scientists to alter the DNA sequence of organisms. This method has multiple applications in our society, including biomedical research and agriculture. In agriculture we can use gene editing to modify and enhance various characteristics of our food by combining or modelling the new DNA off of food that has more desirable characteristics. Another application includes gene editing to aid or enhance biomedical research, by altering the human genome in two ways. The first way an individual’s genome can be altered is within their somatic cells, this altering is commonly referred to as gene therapy. Gene therapy changes the DNA in the somatic cells of an individual with the intent to treat a disease or enhance the individual’s living in some way. Although these changes are permanent they cannot be inherited by offspring, as the alterations are occurring in somatic cells. This form of gene editing is widely supported in the scientific community as a promising treatment for individuals.

The second way that the human genome can be changed is through the modification of germ line cells. This involves changing the DNA of embryos, eggs or sperm before they have develop into an individual. These changes would be inherited in all future generations, regardless to whether the change is beneficial or harmful. There are three potential applications of germ line genome editing(GGE): to cure patients, to avoid the inheritance of gene-linked conditions, and to enhance an embryo for non-medical purposes. Though GGE has the potential to be very helpful it comes with much ethical controversy from the scientific community, and many countries have laws regulating the use of GGE. This brief will give an overview of the most commonly used method of gene editing, CRISPR, and the legal and ethical implications that should be considered when starting a business in GGE.

Methodologies of CRISPR

Genome editing works by acting like scissors. Scientists can go along the DNA, find a specific spot, and then remove, add or replace the DNA where it was cut. There are a multitude of technologies available for gene editing, however CRISPR is currently the most commonly used. CRISPR was designed in 2009 and stands for clustered regularly interspaced palindromic repeats. These repeats are found naturally in bacteria which store information that can help to recognize invading viruses. There are certain enzymes, like a molecule named Cas, that are associated with these repeats that search for a specific DNA sequences and cut precisely at that point. Scientists can adapt these CRISPR-Cas molecules to search for specific DNA sequences in other genomes, such as plants, animals and humans, and cut at those specific points. These molecules can also provide a new DNA sequence for the cell to use when it repairs the cut.

Like any technology, CRISPR can make errors which could have negative effects on the host’s physical expression of the genome. CRISPR sometimes mis-recognizes a DNA sequence that is similar to the one it’s looking for and cuts in the wrong place, resulting in off-target mutations. It may also cut in the right place, but cause mistakes where DNA is incorrectly inserted or deleted.

Legal & Ethical Considerations

Canada is one of few countries in the world with a criminal ban on any form of alteration to human germ line cells. In 2004 the Assisted Human Reproduction Act was put in place, because of public worry of human cloning due to the Human Genome Project, stating that no person shall knowingly […] alter the genome of a cell of a human being or in vitro embryo such that the alteration is capable of being transmitted to descendants. When this ban was put in place there was no distinction or clarification made about how this legislation applied to research, or in a clinical context. However Canadian scientists have not tried to find a loop hole in this legislation because of the heavy sentence it carries. Violators of this offence, if found guilty, are subject to a fine up to $500,000 and/or 10 years in prison.

Other countries have taken a different approach to regulating GGE. The United States, for example, has made the use of genetic engineering techniques to make genetic alterations that can be passed on to future generations illegal. However, scientists are still allowed to conduct research within the field, so long as the experimental embryos never have the chance to become babies. Some countries around the world possess similar bans to the one in Canada, and researchers have still been finding way to do studies. Liang and co-authors have been doing research with GGE on embryos with an extra chromosome, called triple embryos. These embryos could not be carried to term in a pregnancy if they were implanted, meaning there is no risk of babies being born from their research. Additionally their study found a high rate of off-target mutations, however most of these did not result in morally significant harm.

A criminal ban is a suboptimal tool for regulating science for many reasons. Due to the lengthy process in which legislation is made and altered in Canada bans on scientific research can hinder our responsiveness to the continually changing nature of science and societal attitudes. For example, if there were suddenly to be a shift in regulations on GGE, Canadian scientists would be at a disadvantage to other countries would have been allowed to conducted research up until that point. The Law Reform of Canada was a law commission, independent of the government formed to give the Canadian government advice on matters pertaining to law, and it was formed in 1971. In 1982 the Law Reform Commission of Canada stated that criminal law should be “an instrument of last resort used solely for conduct which is culpable, seriously harmful and generally conceived as deserving of punishment”. Canid has also signed several declarations over the years that enforces the right for all Canadian citizens to enjoy the benefits of scientific progress and it’s applications. This begs the question as to whether or not the benefits outweigh the risks in regard to GGE.

130 million babies are born world wide each year, 7 million of those are born with a serious genetic disease that is hereditary. Of this 7 million, approximately 80% of the disorders are caused by single gene mutations. The biggest case for GGE is for parent carriers of these single gene disorders, although it has been argued that in vitro fertilization (IVF) could fix this problem. Although carriers of genetic disease could opt to do IVF, consider this situation. Hypothetically if both parents were carriers for an inherited disease only one in four fertilized eggs would produce an embryo that presents the disease phenotypically. However 19% of women undergoing IVF only produce one viable embryo, and if that one embryo gets two genes for the disease then the parents face the decision of bringing a diseased child into the world, or not having a child at all. GGE would prevent this chance, and therefore that decision from having to be made.

The largest safety and ethical concern associated with genome editing is the off-target mutations that may result from the use of CRISPR-Cas9, the most frequently used editing technology. These off target mutations may cause irreversible changes to the genome that could result in the development of cancer or other pathologies. Not only would these mutations effect the embryo being edited, but possibly all future generations. With any medical procedure there are a number of risks associated, and this risks need to be weighed accordingly.

These risks are not isolated to mistakes in the technology, there are any unknowns about how the technology would impact society. If the criminal ban on GGE is lifted it is quite possible that it would be used as a tool of enhancement, not just preventing disease, which could have a variety of societal repercussions. Not only is it important to consider the preservation of human diversity and individuality, which would likely be compromised. But it is also important to consider how these enhancements will effect future generations. For example, altering or increasing the frequency of certain genes that would be beneficial to the current generation may be harmful to future generations. The question remains, are these risks strong enough to justify prohibiting all forms of GGE?

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