Advances in understanding behavioral phenotypes in neurogenetic syndromes

AbstractSyndrome‐specific behavior was proposed by Langdon Down in his first clinical descriptions. Research interest followed but waned during the eugenics era when antisocial behavior was attributed to people with intellectual disability (ID) and the US Supreme Court legalized involuntary sterilization. When these claims were refuted and behavioral treatments introduced, their focus on environmental determination minimized the importance of biological research. The modern era began with the recognition that patterned behavior, for example, self‐injury in Lesch–Nyhan syndrome and hyperphagia in PWS, was syndrome‐specific, and when parent support groups pointed out syndrome‐specific behavioral similarities in their children. Syndrome‐specific rating scales and methodologies followed to allow behavioral comparisons between syndromes. The focus initially was on specific behaviors but with refinements in neuropsychological tests has expanded to include neurocognitive profiles. Greater clarification in genetic diagnoses has led to mutant mouse behavioral models and neurophysiologic and neuroimaging strategies have made possible the study of brain circuits. There is growing interest in