Many other neurodegenerative
diseases have defects in genes that influence the response of a cell to
injury or cellular protective mechanisms such as free radical protective
enzymes, or involve genes which can be shown
in vitro
to influence apoptosis.
Many of these diseases have catastrophic later onset of illness in
midlife. These illnesses can be viewed as having a secondary genetic relationship
to apoptosis. However, even environmental events in a genetically
neutral or “normal” host can result in apoptosis.