ABSTRACT
Predictive genetic testing for Huntington’s disease (HD) has been performed in the US since the mid-1980s, following the discovery of DNA markers genetically linked to the HD gene. However, widespread use of predictive gene tests for adult-onset neurogenetic disorders did not begin until the 1990s, when the identification of the HD gene and several hereditary ataxia genes permitted individuals to undergo simple and accurate blood tests without requiring multiple family members to participate in the testing process. Centres in both the US and Canada, as in Europe, have attempted to assess the effects of and improve upon the use of this new clinical technology by forming consortia of involved individuals, laboratories and clinical centres. This chapter focuses on the experiences of two such groups, the US Huntington Disease Genetic Testing Group (US HD GTG) and the Ataxia Molecular Diagnostic Testing Group (AMDTG), but will also review the contributions of the Canadian Collaborative Study of Predictive Testing for Huntington Disease and of other individual investigators in Canada, the US and Mexico.
