Overview of the different steps undertaken in the study. Step 1: development of SVM classifier to assess the presence and strength of behavioral signatures among genetic syndromes. Step 2: application of the classifier derived in step 1 to AGRE samples to test if similarity in behavioral signatures can be detected among idiopathic ASD subjects. Step 3: application of classifier derived in step 1 to sibling pairs with idiopathic ASD (AGRE) to test relative familiality of behavioral signatures derived from genetic syndromes. AGRE, Autism Genetics Resource Exchange; ASD, autism spectrum disorder; SVM, support vector machine.