GeneTest Review

Genetics in Medicine (2011) 13, 278–294; doi:10.1097/GIM.0b013e3181ff67ba

Autism spectrum disorders—A genetics review

Judith H Miles1

1Division of Medical Genetics, Department of Child Health, Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri Hospitals and Clinics, Columbia, Missouri

Correspondence: Judith H. Miles, MD, PhD, Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri, 205 Portland, Columbia, MO 65211. E-mail:

Received 26 July 2010; Accepted 30 September 2010; Published online 24 April 2011.

Disclosure: The author declares no conflict of interest.



Abstract: Autism is an etiologically and clinically heterogeneous group of disorders, diagnosed solely by the complex behavioral phenotype. On the basis of the high-heritability index, geneticists are confident that autism will be the first behavioral disorder for which the genetic basis can be well established. Although it was initially assumed that major genome-wide and candidate gene association studies would lead most directly to common autism genes, progress has been slow. Rather, most discoveries have come from studies of known genetic disorders associated with the behavioral phenotype. New technology, especially array chromosomal genomic hybridization, has both increased the identification of putative autism genes and raised to approximately 25%, the percentage of children for whom an autism-related genetic change can be identified. Incorporating clinical geneticists into the diagnostic and autism research arenas is vital to the field. Interpreting this new technology and deciphering autism's genetic montage require the skill set of the clinical geneticist including knowing how to acquire and interpret family pedigrees, how to analyze complex morphologic, neurologic, and medical phenotypes, sorting out heterogeneity, developing rational genetic models, and designing studies. The current emphasis on deciphering autism spectrum disorders has accelerated the field of neuroscience and demonstrated the necessity of multidisciplinary research that must include clinical geneticists both in the clinics and in the design and implementation of basic, clinical, and translational research.


autism; genetics; review; heterogeneity; subgroups