Prenatal Diagnosis is a crucial process involving testing a baby in the pregnant uterus to determine if it has inherited Huntington’s disease. This two-step journey begins with to-be-parents, at least one of whom has a definitive Huntington’s disease diagnosis, being referred to a fetal medicine centre. Here, they engage in a detailed conversation with a genetic counsellor, exploring the pros and cons of testing an unborn fetus for an adult-onset, unpredictable neurological disorder.
Should the parents decide to proceed with prenatal testing, the mother undergoes one of the following procedures following a natural conception:
CVS (Chorionic Villus Sampling):
Typically performed between 10-13 weeks of pregnancy, CVS involves removing a piece of the developing placenta through a woman’s abdomen, using a catheter or needle as the ultrasound probe guides the process. As this tissue is 99 percent genetically identical to the fetus, DNA testing can determine the Huntington’s disease status, providing a conclusive result.

Figure 1: CVS (Chorionic Villus Sampling)
Amniocentesis
Conducted between 15-20 weeks of pregnancy, amniocentesis involves the removal of a small amount of amniotic fluid surrounding the baby using a thin needle, as the ultrasound probe guides the process. Cells from the baby in this fluid can be isolated, grown in the lab, and tested for Huntington’s disease status.

Figure 2: Amniocentesis