What is (are) 7q11.23 duplication syndrome ?
7q11.23 duplication syndrome is a condition that can cause a variety of neurological and behavioral problems as well as other abnormalities.  People with 7q11.23 duplication syndrome typically have delayed development of speech and delayed motor skills such as crawling and walking. Speech problems and abnormalities in the way affected individuals walk and stand may persist throughout life. Affected individuals may also have weak muscle tone (hypotonia) and abnormal movements, such as involuntary movements of one side of the body that mirror intentional movements of the other side.  Behavioral problems associated with this condition include anxiety disorders (such as social phobias and selective mutism, which is an inability to speak in certain circumstances), attention deficit hyperactivity disorder (ADHD), physical aggression, excessively defiant behavior (oppositional disorder), and autistic behaviors that affect communication and social interaction. While the majority of people with 7q11.23 duplication syndrome have low-average to average intelligence, intellectual development varies widely in this condition, from intellectual disability to, rarely, above-average intelligence. About one-fifth of people with 7q11.23 duplication syndrome experience seizures.  About half of individuals with 7q11.23 duplication syndrome have enlargement (dilatation) of the blood vessel that carries blood from the heart to the rest of the body (the aorta); this enlargement can get worse over time. Aortic dilatation can lead to life-threatening complications if the wall of the aorta separates into layers (aortic dissection) or breaks open (ruptures).  The characteristic appearance of people with 7q11.23 duplication syndrome can include a large head (macrocephaly) that is flattened in the back (brachycephaly), a broad forehead, straight eyebrows, and deep-set eyes with long eyelashes. The nose may be broad at the tip with the area separating the nostrils attaching lower than usual on the face (low insertion of the columella), resulting in a shortened area between the nose and the upper lip (philtrum). A high arch in the roof of the mouth (high-arched palate) and ear abnormalities may also occur in affected individuals.