Genetic Defect Linked to Hyperactivity

Scientists have discovered a genetic defect that causes hyperactivity, marking the first time a specific inborn flaw has been linked to a common behavioral problem.

The discovery should allow doctors to spot newborns who are likely to develop the disorder, and it should provide clues about the disorder’s cause and treatment.

Scientists found that attention deficit hyperactivity disorder, as it is formally called, can result from a mistake in a gene that regulates the body’s use of thyroid hormone.

Although this gene probably accounts for only a fraction of cases of hyperactivity, other thyroid hormone problems may turn out to be a factor in many cases, the researchers reported in today’s New England Journal of Medicine.

“Attention deficit disorder is very common. It is unlikely we would find one gene responsible for all children with this,” said Dr. Peter Hauser, the study’s director.

Victims have trouble focusing their attention and controlling impulses, and they tend to be restless and aggressive. Often, they are disruptive in school. Although the disorder is first seen in childhood, it may linger into adulthood.