Rett syndrome is a neurodevelopmental disorder usually caused by a mutation on the X-linked methyl-CpG-binding protein 2 (MECP2) gene.[1] The condition affects females approximately 1 per 9,000 live female births,[2] and is characterized by a loss of functional hand use and language skills in early childhood with the development of hand stereotypies and impaired mobility.[3] These developmental issues are complicated by frequent occurrence of comorbid conditions. The gene discussed is MECP2; the disease is atypical Rett syndrome.