15 Jun 2001

The gene mutation that causes Huntington's disease has been known for many years, yet the function of the encoded protein, huntingtin, and the pathogenic mechanism of the mutant protein, have remained frustratingly elusive. Various studies have shown that mutant huntingtin forms aggregates, which are suspected of being toxic. Now a study published in the current issue of Science indicates a new function for huntingtin: regulating transmission of brain-derived neurotrophic factor (BDNF), a protein that is essential for the survival of the striatal neurons that die in Huntington's. This transcription is impaired with mutant huntingtin, suggesting that loss of BDNF may leave striatal neurons vulnerable. The new finding raises the possibility of treating Huntington's with drugs or gene therapies that deliver BDNF to at-risk neurons.—June Kinoshita