The first session of the final day at the CHDI meeting focused on restoring neuronal networks. Most of these methodologies focus on the once fanciful idea that damaged neurons in the brain can be replaced with healthy new ones.

Work by Ali Brivanlou using embryonic stem cells (cells which may be nurtured to grow into any cell type) mutated to carry the HD CAG-expanded gene, has allowed close study of how this mutation may affect development. Given the critical role huntingtin has in development (removing the gene entirely is lethal to the developing organism in many cases), this work should shine a light into what huntingtin is doing in these early stages of growth. This is also a great model in which to study HD as mouse models often do not reflect the same characteristics as humans (unsurprisingly!) so the results are more relevant to the human disease.

Ann Graybiel gave a fantastically interesting presentation on emotional problems experienced by HD patients, linked to potential dysfunction of the basal ganglia, the most vulnerable part of the brain in this disease. Graybiel’s work continues to develop tools to see how this part of the brain and its associated processes are affected by the introduction of the mutated HD gene.

The afternoon session focused on clinical trial methodology for HD i.e. what are the best measurements to make and how do we interpret this data. Currently the overlap in methods across different HD clinical trials is fairly small making a meta-analysis (analysis of all the available data) particularly tricky.

Jianying Hu from IBM’s Watson Lab is using computer algorithms to analyse all of the available data from HD clinical trials in order to help assess different HD states, transitions between these states and also predict future outcomes for HD patients. This could potentially be very useful for clinical assessment.