What Research Is Being Done?
 

Within the Federal Government, the National Institute of Neurological Disorders and Stroke (NINDS), one of the National Institutes of Health (NIH), has primary responsibility for conducting and supporting research on normal and abnormal brain and nervous system development, including congenital anomalies. The National Institute of Child Health and Human Development, the National Institute of Mental Health, the National Institute of Environmental Health Sciences, the National Institute of Alcohol Abuse and Alcoholism, and the National Institute on Drug Abuse also support research related to disorders of the developing nervous system. Gaining basic knowledge about how the nervous system develops and understanding the role of genetics in fetal development are major goals of scientists studying congenital neurological disorders.

Scientists are rapidly learning how harmful insults at various stages of pregnancy can lead to developmental disorders. For example, a critical nutritional deficiency or exposure to an environmental insult during the first month of pregnancy (when the neural tube is formed) can produce neural tube defects such as anencephaly.

Scientists are also concentrating their efforts on understanding the complex processes responsible for normal early development of the brain and nervous system and how the disruption of any of these processes results in congenital anomalies such as cephalic disorders. Recently, two new genes have been discovered that are causes of lissencephaly and milder neuronal migration disorders. Understanding how genes control brain cell migration, proliferation, differentiation, and death, and how radiation, drugs, toxins, infections, and other factors disrupt these processes will aid in preventing many congenital neurological disorders.

Currently, researchers are examining the mechanisms involved in neurulation—the process of forming the neural tube. These studies will improve our understanding of this process and give insight into how the process can go awry and cause devastating congenital disorders.

Investigators are also conducting a variety of genetic studies. One of these studies concentrates on a specific form of holoprosencephaly with the goal of finding the basic DNA defect responsible for the abnormal development seen in this disorder. Researchers are also analyzing genes and gene products necessary for human brain development to achieve a better understanding of normal brain development in humans.

Other research projects currently under way include a study to evaluate increased risk of neural tube defects and various other congenital malformations in association with environmental and occupational exposure to pesticides.