The present invention relates generally to efficient delivery of viral vectors to cells of the CNS, particularly useful in the treatment of neurodegenerative disorders and
motor neuron diseases. The invention involves selecting a first
population and a second
population of synaptically connected neurons, wherein a therapeutic polypeptide is to be expressed in said second
population of neurons; and administering rAAV virions comprising a therapeutic
gene to said first subpopulation of neurons of said subject such that the rAAV virions are transported across a
synapse between synaptically connected neurons. In another aspect the present invention also comprises the use of rAAV virions carrying a
transgene in the preparation of a medicament for the treatment of a
disease in a subject, wherein a first population and a second population of synaptically connected neurons are selected and a therapeutic polypeptide is to be expressed in said second population of neurons; and a medicament comprising recombinant adeno-associated
virus (rAAV) virions is delivered to said first population of neurons of the subject, wherein said virions comprise a
nucleic acid sequence that is expressible in transduced cells to provide a
therapeutic effect in the subject, and wherein said rAAV virions are capable of transducing a synaptically connected neurons.