Children of positive carriers
Testing minors for Huntington disease is contraindicated. If a parent is a carrier or already has the disease, it is advisable to allow their minor children to grow up and decide for themselves whether they want to be tested. Because of the possibility of a treatment for Huntington disease in the future, there is no need to burden children with the knowledge of being a gene carrier, especially since the disease will probably not develop until they are in their late 30s or 40s.4
In general, people at risk have been familiar with the symptoms since childhood. They experience stressors that may involve their relationship with the affected parent, who may be preoccupied with her or his condition and experiencing depression or agitation as a symptom of the disease. Moreover, the choreic movements may frighten children. Family dynamics are disturbed and must be addressed in counseling, in addition to providing support and up-to-date genetic information about the disease.
Who should undergo testing for Huntington disease?
Generally, testing should be performed in the following settings4:
• Individuals at risk, who should be tested as adults not as minors
• Prenatal testing, which is best performed before high-risk candidates plan to have a child
• Preimplantation genetic diagnosis, which is an option when in vitro fertilization is used
• Confirmation of the diagnosis
Genetic, psychological, and family counseling, as well as neurological assessment must be employed. Support should be given to the patient and the carrier.
Dr Bishay reports no conflicts of interest concerning the subject matter of this article.
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