MECP2 duplication syndrome

MECP2 duplication syndrome, sometimes abbreviated M2DS, is a rare disease characterized by severe intellectual disability and impaired motor function. It is an X-linked genetic disorder caused by the overexpression of the MECP2 gene. The name refers to the extra copy of that gene that leads to this overexpression. Because the gene lies on the X chromosome, the condition follows an X-linked pattern of inheritance, and its recognised features centre on the combination of profound learning difficulty and difficulty with movement. The lead description of the disorder does not give further detail beyond these defining features.