The early identification of temperament endophenotypes in ASD

The extensive clinical heterogeneity of autism complicates the search for its causes. Current research is trying to minimize this heterogeneity by identifying meaningful subcategories within autism, or "endophenotypes." These endophenotypes can be based on different characteristics, such as morphology, physiology or behavior, and individuals in the same endophenotype may share the same cause for their autism. New research is suggesting an endophenotype based on temperament, in which members of this subgroup share the traits of flat affect, high anxiety, and poor control of attention.

Previous research from Dr. Bryson's lab has found that high-risk infants (siblings of children with autism) who fit this temperament profile go on to develop autism. In some cases, autism was diagnosed as early as 6-12 months of age. In this new study Dr. Bryson's post-doctoral fellow will test the reliability of this endophenotype by following this same group of high-risk children into preschool. Their temperament will be measured by parent reports, direct observations of behavior, and physiological measures such as heart rate and brain activity.

What this means for people with autism: Most importantly, a temperament endophenotype can potentially allow earlier detection of autism and a more tailed intervention. Identifying reliable endophenotypes in autism can also simplify the search for autism's causes.