Study Finds Link Between Genetic Variations, Stuttering
Mutations in GNPTAB, GNPTG have previously been linked to mucolipidosis types II and III
WEDNESDAY, Feb. 10 (HealthDay News) -- Some cases of stuttering may be related to variations in genes that play a role in lysosomal metabolism, according to research published online Feb. 10 in the New England Journal of Medicine.
Changsoo Kang, Ph.D., of the National Institute on Deafness and Other Communication Disorders in Bethesda, Md., and colleagues analyzed data from stuttering cases in Pakistan, the United States, and England, and controls from Pakistan and North America.
In a large, consanguineous Pakistani family, the authors found a missense mutation in the GNPTAB gene that was associated with stuttering. They also found it and three other GNPTAB mutations in other unrelated stuttering cases, but not controls. The researchers also found mutations in the GNPTG and NAGPA genes. GNPTAB and GNPTG encode subunits of GlcNAc-phosphotransferase, and mutations in them have been associated with mucolipidosis types II and III, which are lysosomal storage disorders.
"Why would dysfunction of a basic process found in many cell types selectively affect the neural circuits involved in speech fluency? Do other undiscovered genes associated with stuttering have roles in metabolic pathways? Can these data explain whether early stuttering will persist? Are there new prospects for treatment? As with other neurodevelopmental disorders that affect speech, the task of connecting the dots between genes and stuttering is just beginning," writes the author of an accompanying editorial.