Huntington's disease (HD) is a genetic neurodegenerative disease. Carriers of the HD gene without clinical symptoms of the disease can be identified and studied. The study of these premanifest... Show moreHuntington's disease (HD) is a genetic neurodegenerative disease. Carriers of the HD gene without clinical symptoms of the disease can be identified and studied. The study of these premanifest subjects is of importance for the understanding of preclinical disease progression and for the design of future clinical trials. HD is characterized by progressive decline in motor functioning, cognition and behaviour. The unwanted motor disturbances that patients experience are likely to be of influence on cognitive functioning, as cognitive tests almost always require a motoric response. In this thesis we investigated cognitive functioning in both premanifest HD gene carriers and HD patients by taking into account the motor disturbances that have been reported in both pre- and manifest phases of the disease. We also reports on the influence of time on cognition in HD by means of several longitudinal reports with follow-up periods as long as ten years. We found both carriers and patients deteriorate most on memory and executive functioning domains, with the latter being most sensitive in the premanifest phase. We have also found evidence for the presence of premanifest (cognitive) compensatory mechanisms. As expected, there is a substantial (negative) effect of motor functioning on cognition in HD. Show less
The aim of the studies described in this thesis was to investigate how abnormal CaV2.1 channel function can cause disease, in particular motor coordination dysfunction. The chapters illustrate how... Show moreThe aim of the studies described in this thesis was to investigate how abnormal CaV2.1 channel function can cause disease, in particular motor coordination dysfunction. The chapters illustrate how various neuronal cell types in the periphery (peripheral nervous system) and the central nervous system are affected by mutations in subunits of CaV2.1 channels. Using existing and newly generated mouse models, the consequences of such mutations were investigated at the molecular, cellular, and systems level so as to unravel pathways involved in motor coordination. Show less