In House M.D., what disease does Dr. Hadley fear inheriting from her mother?

Dr. Remy Hadley fears inheriting Huntington’s disease in House M.D.

Hadley, known as Thirteen, learns that her mother had Huntington’s disease, a hereditary neurodegenerative disorder. This creates a continuing personal conflict because she may carry the disease-causing gene but cannot know with certainty when or whether symptoms will appear without genetic testing.

The storyline is medically significant because Huntington’s disease is usually inherited in an autosomal dominant pattern. A child of an affected parent has a 50 percent chance of inheriting the altered gene, although the timing and severity of symptoms can vary. The series uses this risk to explore privacy, relationships, reproductive choices, and the emotional burden of predictive testing.

Thirteen’s concern is not Parkinson’s disease or Alzheimer’s disease. Those conditions can also affect movement or cognition, but they are distinct disorders and do not explain the specific family-history plot in House M.D.