EFNS guidelines on the molecular diagnosis of neurogenetic disorders: general issues, Huntington's disease, Parkinson's disease and dystonias.

These EFNS guidelines on the molecular diagnosis of neurogenetic disorders are designed to provide practical help for the general neurologist to make appropriate use of molecular genetics in diagnosing neurogenetic disorders. Since the publication of the first two EFNS-guideline papers on the molecular diagnosis of neurological diseases in 2001, rapid progress has been made in this field, necessitating an updated series of guidelines. Literature searches were performed before expert members of the task force wrote proposals, which were discussed in detail until final consensus had been reached among all task force members. This paper provides updated guidelines for molecular diagnosis of Huntington's disease, Parkinson's disease and dystonias as well as a general introduction to the topic. Possibilities and limitations of molecular genetic diagnosis of these disorders are evaluated and recommendations are provided.