Huntington's disease and cell therapies: past, present, and future.

Huntington's disease (HD) is an inherited neurodegenerative disease that is characterized by movement abnormalities, cognitive impairment, and abnormal behavior as well as sleep and weight problems. It is an autosomal dominant disorder caused by a mutation in the huntingtin gene on the short arm of chromosome 4, which results in the progressive degeneration of the basal ganglia (caudate, putamen, and globus pallidus), cerebral cortex, brainstem, thalamus, and hypothalamus. This chapter considers four avenues of research: (a) the restoration of neurogenesis as an endogenous cell therapy in HD, (b) fetal tissue transplantation, (c) stem cell transplantation, and finally (d) the use of endogenous trophic factors such as brain derived neurotrophic factor.