Researchers from the University of Alabama in the United States looking at “the typical range of social communicative impairments observed in children, adolescents, and young adults with DS [Down’s syndrome] who do not have comorbid ASD [autism spectrum disorder]” recently reported that quite a few people diagnosed with Down’s syndrome present with issues with social communication skills more frequently noted in cases of autism*.
Drawing on data derived from 46 participants diagnosed with DS but not passing screening thresholds for a possible diagnosis of an ASD, researchers analysed scores based on the Social Responsiveness Scale (SRS), a parent/caregiver report schedule that measures “aspects of reciprocal social behaviors”. Higher scores on the SRS map on to some of the core domains of autism presentation.
They found that even where possible dual cases of DS and ASD were excluded from their analysis, those with DS were reported to show social behaviour patterns “falling into the mild-to-moderate symptom severity category” of autism. Further, the authors concluded that the use of the SRS in cases of DS may be likely to show a ‘false positive’ if used as an ASD screening instrument in this population.
Such results add to some increasing interest in the presence of autistic traits in cases of DS, a genetic condition caused by the presence of an extra chromosome (chromosome 21) in the cells of the body. Although the authors caution at drawing too many conclusions from the 8 participants originally included in their study who exceeded predetermined cut-off scores when screening for an ASD, their findings might suggest that autism may not be uncommon in cases of DS. Certainly a diagnosis of DS does not seem to offer any protection against receipt of a diagnosis of autism or the appearance of some of the traits of autism.
* Channell MM. et al. Patterns of autism spectrum symptomatology in individuals with Down syndrome without comorbid autism spectrum disorder. Journal of Neurodevelopmental Disorders 2015, 7:5.
Read more about this study here: http://questioning-answers.blogspot.com/2015/01/autism-spectrum-symptomatology-in-downs-syndrome.html