Huntington's Disease; power and duty of parents over offsprings

by Yuxi_Liu 3 min read21st May 20198 comments


Huntington's Disease

Basic facts about Huntington's Disease:

  • Huntington's Disease is an inherited disorder that results in death of brain cells.
  • Symptoms usually begin between 30 and 50 years of age, death typically occurs fifteen to twenty years later.
  • A child of an affected person has a 50% chance of inheriting the disease.
  • Diagnosis is by genetic testing, which can be carried out even in embryo
  • There is no cure.

Genetic gross negligence

I was listening to a podcast about Huntington's Disease. In the podcast, there was a man with HD talking, and he said that his daughter had already had 3 children and doesn't want to test for HD, because

  1. If she tested HD-positive, she would not have more children.
  2. She wants to have more children.
  3. Thus, she does not want to test for HD.

The child of a person with a 50% prior probability of having Huntington's disease, has a 25% probability of having Huntington's disease. As such, if parents have some legal duty to give their offspring a decent life, then for people with a high probability of Huntington's Disease to have children without doing genetic testing first, could be considered a form of gross negligence:

a conscious, voluntary act or omission in reckless disregard of a legal duty and of the consequences to another party.

This problem of gross negligence becomes even stronger when one considers the possibility of embryo genetic testing and selective abortion.

Behavioral aspects of HD

In 2018, a woman sued doctors, because they failed to tell her about her father’s fatal hereditary disease before she had her own child.

What is quite interesting in this case is that

The woman’s father shot and killed his wife in 2007 and was convicted of manslaughter. Two years later, doctors at St George’s Hospital in south London found he had Huntington’s disease and asked him to tell his daughter about his condition and her risk of developing it. But he refused to do so because he thought she might abort the child she was carrying. The doctors accepted his decision.

The behavioral aspects of HD are usually the first signs of this disease, and usually diagnosed as psychiatric: The frontal cortex and the criminal justice system (Sapolsky, 2000)

In a sizeable percentage of patients, these motoric symptoms are preceded a few years earlier by damage to the frontal cortex and associated changes in personality. Such changes typically involve marked social disinhibition, increases in aggressiveness and hypersexuality, patterns of impulsivity and poor social judgement.

Possible fitness of HD

HD has a surprisingly high level of prevalence (around 1 per 10000) despite its severe health consequences. This suggests that HD might have some evolutionary fitness that keeps it in the gene pool.

The behavioral aspects of HD noted in the last section plays well along the idea that people with HD have more children on average.

Power and duty of human parents

Duty to offsprings

Pregnant people are subject to long lists of prohibitions and advises, to provide the best womb-environment. They often do it to themselves, but people around them also do that, because healthy offsprings is a social good, and thus enforcing the rules for making healthy offsprings is a social norm.

This prenatal norm enforcement can be seen as an extension of child-raising norm enforcement. Parents are required to give their children good food, shelter, education, medicine, emotional support, etc.

It's strange how many restrictions that pregnant women are being placed under: no alcohol, no thalidomide, no this no that, but 50% of Huntington's gene? That's possibly fine. This is odd.

An extension of the idea that parents have a duty to give their offsprings good lives, would give an argument for one form of eugenics as a duty of parents. Julian Savulescu is one particular advocate:

Principle of Procreative Beneficence (PB): couples who decide to have a child have a significant moral reason to select the child who, given his or her genetic endowment, can be expected to enjoy the most well‐being.

Power over offsprings

As to the exposure of children, let there be a law that no deformed child shall live. -- Aristotle

The moral status of human fetuses and babies is not universal among humans. On one extreme, they are a special form of livestock, host animals in which a person gradually grows. On another extreme, they are 100% person, complete with a true unchanging self (some kind of preformationism). Intermediate positions vary widely, and are often used during abortion debates (Even though abortion debates are motivated by moral emotions, they are played out via moral philosophies.).

I remember reading a story about a future where people can live indefinitely from a genetic therapy before birth. But this failed on a newborn human, who would grow old and die in about 100 years. He became a global celebrity and his graceful death was televised. This started a wave of people who requested for their children to not receive the immortality genetic therapy.

The story is a celebration of antivaccination death cult, as well as illustrating a popular philosophical objection to vaccination: it is unnatural to be vaccinated against natural diseases.

I think this is connected. It shows that parents are thought to have a kind of total pseudorandom right over their offsprings, often called "reproductive right": a human social norm, whereby fertile humans can mate and produce offsprings anywhere and in any manner, as long as they are "natural". Heritable diseases, heritable mortality, they are all genetic and beyond human control, and thus considered natural.