With the knowledge that common environmental assaults on the nervous
system as well as the complex process of cell injury and glial response can
produce both apoptotic cell death and necrotic cell death, there is a real issue
of assessing the role of apoptotic cell death for a given neurodegenerative
disease. The most convincing case can be made for those illnesses with a
genetic defect in a gene directly related to the apoptotic cell response (e.g.,
Batten disease). Not surprisingly, such a major genetic influence on apoptosis
is associated with onset of disease in early life.