Prenatal diagnosis requests for Huntington's disease when the father is at risk and does not want to know his genetic status: clinical, legal, and ethical viewpoints

Huntington's disease is an autosomal dominant, incurable neurodegenerative disorder caused in virtually all cases by a trinucleotide repeat expansion in the IT15 gene. 1 2 Predictive and prenatal testing are available through clinical genetics units, but most people at risk choose not to have predictive testing. 3

Predictive testing is undertaken according to international guidelines, which make recommendations on providing information and counselling support throughout the testing process. 4 The principle of respect for autonomy is protected by allowing people to refuse to have genetic testing after they have been counselled.

Summary points

When the father is at 50% risk of having Huntington's disease, there is a 1 in 4 chance that prenatal testing will show that he has the mutation and will develop the disease

Testing for Huntington's disease normally follows international guidelines that protect an individual's right to know or not know their genetic status

It is unclear whether prenatal testing should be done without the consent of the man at risk

Either performing the prenatal test or refusing it if the man at risk does not consent are legally acceptable

Hypothetical case

Clinical genetics units sometimes face situations such as the one outlined in the following hypothetical case. 5 A woman who is eight weeks pregnant discovers that her partner is at 50% risk of developing Huntington's disease. He is not interested in pursuing predictive testing. The woman is adamant that she does not want a child who will develop Huntington's disease in later life, and she requests a prenatal test.

There is a 1 in 4 chance that the prenatal test will show that the fetus has the mutation for Huntington's disease, and therefore the test also presymptomatically diagnoses the father. Such prenatal requests highlight the uncertainty of the legal position taken by the international guidelines. Cases like this pose considerable ethical and legal dilemmas for clinicians. Does the right of the pregnant mother to know the status of her fetus outweigh the right of the father at risk to not know his genetic status?

In a clinical ethics consultation the lawyer and ethicist presented the clinical team with their ideas on the subject and had the team reconsider its procedures in the light of the different viewpoints.

Clinical team's viewpoint