Please cite this article as follows: Taniai H, Nishiyama T, Miyachi T, Imaeda M, Sumi S. 2008. Genetic Influences on the Broad Spectrum of Autism: Study of Proband-Ascertained Twins. Am J Med Genet Part B 147B:844–849.
Genetic influences on the broad spectrum of autism: Study of proband-ascertained twins†
Article first published online: 24 MAR 2008
Copyright © 2008 Wiley-Liss, Inc.
American Journal of Medical Genetics Part B: Neuropsychiatric Genetics
Volume 147B, Issue 6, pages 844–849, 5 September 2008
How to Cite
Taniai, H., Nishiyama, T., Miyachi, T., Imaeda, M. and Sumi, S. (2008), Genetic influences on the broad spectrum of autism: Study of proband-ascertained twins. Am. J. Med. Genet., 147B: 844–849. doi: 10.1002/ajmg.b.30740
- Issue published online: 22 AUG 2008
- Article first published online: 24 MAR 2008
- Manuscript Accepted: 23 JAN 2008
- Manuscript Received: 11 JUN 2007
- structural equation modeling;
- additive genetics influences;
- non-shared environmental influences
An investigation of genetic structures underlying autistic traits was performed with samples from twins for which at least one proband had been ascertained as having autism spectrum disorders (ASDs) in our catchment area. In order to adjust for recent concepts of autism, we employed criteria for the broad spectrum of disease and the childhood autism rating scale (CARS) for quantitative assessment. The CARS test was performed on 45 twin pairs (19 monozygotic, 26 dizygotic) detected with a regional routine screening system. The obtained CARS scores were subjected to structural equation modeling (SEM), incorporating sex differences for each causal influence ascertainment correction, using the Mx software. A best fitting model of causal influences on autistic traits measured continuously, incorporating additive genetic (A) and non-shared environmental influences (E), was generated. With this AE model, the estimated heritability was 0.73 for males and 0.87 for females, based on the continuous CARS scores. There was no evidence for the existence of sex-specific genetic influences. Autistic traits were highly heritable in twins with even broad spectrum of autism, corresponding to the results of early studies based on classical autism. Additive genetic factors were more influential in females than males. © 2008 Wiley-Liss, Inc.