Olfactory function in Huntington's disease patients and at-risk offspring.

Odor identification ability and detection threshold sensitivity were measured in 25 probands with Huntington's disease, 12 at-risk offspring, and 37 unrelated controls. Relative to controls and at-risk offspring, HD patients exhibited significant impairment on both measures of olfactory function. By contrast, at-risk offspring did not evidence any olfactory impairment relative to controls. Thus, impaired olfactory function does not aggregate in the family members of HD patients, and does not serve as an indicator of genetic vulnerability to the disorder.