Proximal 16p11.2 microduplication syndrome is a rare chromosomal anomaly syndrome resulting from a partial duplication of the short arm of chromosome 16 characterized by developmental delay and intellectual disability of a highly variable degree, autism spectrum, obsessive-compulsive, attention deficit hyperactivity disorder, speech articulation abnormalities, muscular hypotonia, tremor, hyper- or hyporeflexia, seizures, microcephaly, neuroimaging abnormalities, decreased body mass index and schizophrenia or bipolar disorder later on in life. The disease is MONDO_0013847 (chromosome 16p11.2 duplication syndrome). Also known as: proximal 16p11.2 microduplication syndrome, proximal dup(16)(p11.2), proximal trisomy 16p11.2.