World Health Organization

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TOPIC 1 – Mitochondrial transfer and three-parent babies

In the fall of 2016, the world’s first baby to undergo a successful mitochondrial transfer procedure was born. Mitochondrial transfer is an experimental in-vitro fertilization (IVF) treatment that involves using the DNA from 3 individuals – a biological mother, a biological father, and a mitochondrial DNA donor – to create an embryo. Babies born from embryos which have undergone this procedure are commonly referred to as “three-parent babies”.

Humans have two types of DNA, nuclear DNA (nDNA) and mitochondrial DNA (mDNA). Whereas nDNA contains the 46 chromosomes that make up the human genome, mDNA contains only the genes required for the proper function of mitochondria. Mitochondria are organelles, and the energy producers of our individual cells. Since human eggs contain mDNA but sperm do not, mDNA is inherited from the mother. While nDNA and mDNA are separate entities, they are in constant interaction with each other within human cells.

Mitochondrial transfer is a technique designed to prevent the transmission of genetic defects in mDNA to one’s offspring. It is a form of IVF wherein a mother’s nDNA is extracted from one of her eggs, and inserted into the egg of a donor. This new egg, containing the heathy nDNA from the biological mother and healthy mDNA from the donor, is fertilized by the biological father’s sperm, and implanted back into the biological mother. The first known successful mitochondrial transfer was performed by American physician Dr.John Zhang in Mexico, and has been hailed as a breakthrough in reproductive technologies aimed at assisting mothers at risk of passing on potentially fatal mDNA defects to their children. As of August 2017, mitochondrial transfer is only explicitly legal in the United Kingdom.

However, the technique is not without controversy. Individuals born out of mitochondrial transfer techniques undergo permanent genetic modification, and the potential health risks of this are not yet understood. While proponents of mitochondrial transfer argue that the treatment falls under women’s reproductive rights and therefore should be protected, some bioethicists counter that the technique should be considered eugenics, as it alters the human germline. Bioethicists also warn that mitochondrial transfer is unfair to the children born out of it, as these children bear essentially all the risk of future complications. The medical community is divided over whether mitochondrial transfer should be suspended until the baby born under Dr. Zhang’s care can be comprehensively observed for long-term side-effects, or whether it should immediately become a widespread treatment due to its lifesaving potential for children who would otherwise be born with fatal mDNA defects.

Further, there are concerns that arise out of the decision to perform the treatment in Mexico. The procedure was performed in Mexico because, as Dr. Zhang put it, “there are no rules [in Mexico]”. Observers worry that by performing experimental treatments in jurisdictions with little regulation, consideration of the experiment by Ethics Review Boards may not be adequately stringent. Some argue that by swiftly legalizing controversial experimental treatments in countries such as the United States, potential risks will be better mitigated since researchers will be less likely to perform experiments in jurisdictions that are much less highly regulated and supervised.

Two major issues, among others, stand out for the WHO do address:

  1. To what extent is genetic modification of the human germline ethical?
    1. Does endorsing techniques such as mitochondrial transfer risk setting a precedent for then endorsement of full-fledged ‘designer babies’ and eugenics?
    2. Should genetic modification to nDNA vs mDNA be treated differently?
  2. What regulations, if any, should be put in place to govern novel reproductive treatments?
    1. Should universal regulation/supervison policies be put in place to avoid jurisdictional inconsistencies?

TOPIC 2 – The question of mandatory vaccination

Worldwide vaccination efforts are responsible for the tremendous reduction in deaths from preventable diseases over the past several decades. With the eradication and near-eradication of smallpox and polio respectively, as well as the increasingly widespread immunization against diseases such as measles, yellow fever, tetanus and whooping cough, millions of lives are saved every year.

Disease risk reduction is most effective when vaccination rates in a community reach the rates required for ‘herd immunity’. Herd immunity relies on the fact that when the vast majority of a community is protected against disease, the opportunity for disease outbreak is greatly reduced. Further, by preventing outbreaks, populations that are not eligible for vaccines, such as children and individuals with immunocompromising conditions, gain protection against infection too.

Despite the evidence for its effectiveness in improving public health, vaccination is not fully mandatory in most jurisdictions. Although many western countries have compulsory vaccination laws, many allow individuals to be exempted for philosophical and religious reasons. That said, western countries typically have fairly high vaccine compliance rates. Compliance is much less consistent in developing countries, especially in rural areas, where access to health care is often limited.

However, vaccination has been met with skepticism by some groups, both in westernized and developing countries. In the west, as ‘anti-vax’ groups claim that vaccines can cause autism and other conditions in children, vaccination compliance rates have fallen below the levels required for herd immunity in many areas. In developing countries, vaccination initiatives are often met with mistrust. This mistrust is rooted in the historical social context of inequality between the western and developing world. Vaccines are often seen as a ploy to sterilize non-western populations, and in the early 2000s some groups claimed there was a link between polio vaccination and HIV infection. Additionally, objection to vaccination for religious reasons occurs worldwide.

Two major issues, among others, stand out for the WHO to address:

  1. To what extent should individual rights be limited in order to promote public health?
    1. Does the human cost of disease ever outweigh the rights of individuals to exercise their rights to bodily autonomy and freedom of religion?
    2. Should non-vaccinated individuals be excluded from certain public institutions, such as schools?
  2. What is the best way to promote the benefits of vaccination in anti-vax environments?
    1. Which policies should be recommended to governments to increase vaccination compliance rates (incentive programs, public education initiatives, etc)?
    2. How can vaccination proponents be protected against abuse and/or violence in high-risk environments?