Whilst pro-caspase-6 expression is low in the fetal and adult human brain [15], caspase-6 has been shown to be crucial in neurodegenerative disorders such as Huntington's, Alzheimer's and Parkinson's disease [16,17], in age-related memory decline [18], following adult stroke [19], and in hippocampal epileptogenesis and epilepsy [20]. This evidence concerns the gene CASP6 and Parkinson disease.