Cognitive and neurological aspects of sex chromosome aneuploidies.

Sex chromosome aneuploidies are a common group of disorders that are characterised by an abnormal number of X or Y chromosomes. However, many individuals with these disorders are not diagnosed, despite established groups of core features that include aberrant brain development and function. Clinical presentations often include characteristic profiles of intellectual ability, motor impairments, and rates of neurological and psychiatric disorders that are higher than those of the general population. Advances in genetics and neuroimaging have substantially expanded knowledge of potential mechanisms that underlie these phenotypes, including a putative dose effect of sex chromosome genes on neuroanatomical structures and cognitive abilities. Continuing attention to emerging trends in research of sex chromosome aneuploidies is important for clinicians because it informs appropriate management of these common genetic disorders. Furthermore, improved understanding of underlying neurobiological processes has much potential to elucidate sex-related factors associated with neurological and psychiatric disease in general.