Research findings about handedness in sydromes associated with intellectual disability are ambiguous. We investigated the frequency of handedness in three syndromes associated with intellectual disability. A total of 80 age and gendre matched children and adolescents, (20 with Down syndrome, 20 with Sotos syndrome, 20 with Williams syndrome and 20 with typical development), participated in this study. Handedness was defined according to the Edinburgh Handedness Inventory and α classification we developed representing levels of handedness. Using the Laterality Quotients calculated for each group, we didn’t find significant differences between these syndromes. However, our data indicate that atypical laterality between the three syndromes does not occur at the same rate, suggesting the existence of specific patterns of laterality in each syndrome, probably related to the underlying genetic basis.
Keywords: Syndrome, down syndrome, genetic syndromes, hand preference, intellectual disability., sotos, williams syndrome