Genetic Etiology in Cases of Recovered and Persistent Stuttering in an Unselected, Longitudinal Sample of Young Twins Purpose The contribution of genetic factors in the persistence of and early recovery from stuttering was assessed. Method Data from the Twins Early Development Study were employed. Parental reports regarding stuttering were collected at ages 2, 3, 4, and 7 years, and were used to classify speakers into ... Research Article
Research Article  |   May 01, 2007
Genetic Etiology in Cases of Recovered and Persistent Stuttering in an Unselected, Longitudinal Sample of Young Twins
 
Author Affiliations & Notes
  • Katharina Dworzynski
    King’s College London, London, England
  • Anna Remington
    University College London
  • Frühling Rijsdijk
    King’s College London
  • Peter Howell
    University College London
  • Robert Plomin
    King’s College London
  • Contact author: Peter Howell, Department of Psychology, University College London, Gower Street, London WC1E 6BT, England. E-mail: p.howell@ucl.ac.uk.
Article Information
Speech, Voice & Prosodic Disorders / Fluency Disorders / Special Populations / Genetic & Congenital Disorders / Research Articles
Research Article   |   May 01, 2007
Genetic Etiology in Cases of Recovered and Persistent Stuttering in an Unselected, Longitudinal Sample of Young Twins
American Journal of Speech-Language Pathology, May 2007, Vol. 16, 169-178. doi:10.1044/1058-0360(2007/021)
History: Received December 8, 2005 , Revised July 7, 2006 , Accepted December 5, 2006
 
American Journal of Speech-Language Pathology, May 2007, Vol. 16, 169-178. doi:10.1044/1058-0360(2007/021)
History: Received December 8, 2005; Revised July 7, 2006; Accepted December 5, 2006
Web of Science® Times Cited: 46

Purpose The contribution of genetic factors in the persistence of and early recovery from stuttering was assessed.

Method Data from the Twins Early Development Study were employed. Parental reports regarding stuttering were collected at ages 2, 3, 4, and 7 years, and were used to classify speakers into recovered and persistent groups. Of 12,892 children with at least 2 ratings, 950 children had recovered and 135 persisted in their stutter.

Results Logistic regressions showed that the rating at age 2 was not predictive of later stuttering, whereas ratings at ages 3 and 4 were. Concordance rates were consistently higher for monozygotic than for dizygotic twin pairs (with the exception of girls at age 3). At 3, 4, and 7 years, the liability to stuttering was highly heritable (h2 estimates of between .58 and .66). Heritability for the recovered and persistent groups was also high but did not differ from each other.

Conclusion Stuttering appears to be a disorder that has high heritability and little shared environment effect in early childhood and for recovered and persistent groups of children, by age 7. The clinical implications of the findings are discussed.

Acknowledgments
The first author was funded by a National Alliance for Autism Research project grant. The second and fourth authors were funded by Wellcome Trust Program Grant 072639. TEDS is funded by MRC Program Grant G9424799. Many thanks for the support of the TEDS staff group and to Susan Felsenfeld for their helpful comments. We also thank the parents of the TEDS twins for their participation. Parts of these data were presented at the 5th Speech Motor Control Conference in Nijmegen, The Netherlands, June 2006.
Order a Subscription
Pay Per View
Entire American Journal of Speech-Language Pathology content & archive
24-hour access
This Article
24-hour access