By Dennis Drayna, Ph.D.
Recent research in Cameroon, West Africa, has uncovered the existence of an entire group of previously unknown families in which
stuttering occurs as a simple inherited trait. Through the cooperation of the Speak Clear Association of Cameroon (SCAC) and the Stuttering Home Page maintained at Mankato State University, researchers had previously identified a single Cameroonian family of 100 individuals, 45 of whom stutter.
This unusual family motivated more field studies in Cameroon. These studies have now shown that as remarkable as this family is, they're not unique. Researchers have now identified 4 additional large families, ranging in size from 25 to 80 individuals, and in all
of these families, almost half of the individuals stutter. All the families found so far come from a single region in Cameroon's Northwest Province, suggesting there might be some common inherited factor at work in
"These families provide hope that we'll be able to identify the gene that appears to be at work to cause stuttering in these families" said Dr. Dennis Drayna, who works at the National Institute on Deafness and Other Communication Disorders, in Bethesda, Maryland. "Even though most stuttering doesn't seem to occur in such large family groups, finding the cause of stuttering in these families may provide important clues to the identity of other causes of this puzzling disorder", he said.
This work is supported by the National Institutes of Health.