Cell death in normal and abnormal development

Research over the past 50 years has consistently documented that cell death is an integral part of both normal development and the etiology of birth defects; however, the significance of this cell death has been, until recently, unclear. Research published during the past 15 years has now shown that programmed cell death (PCD) and teratogen-induced cell death are genetically controlled processes (apoptosis) that play important roles in both normal and abnormal development. Therefore, the purpose of this review is to highlight what is known about PCD and teratogen-induced cell death and their relationships to the mechanisms of apoptosis and abnormal development.