Manken Disease is an extremely rare, genetic disorder characterized by progressive degeneration of the nervous system. It is caused by a mutation in the GJC2 gene, which affects the production of a particular type of protein. Symptoms typically begin in early childhood and include seizures, cognitive impairment, poor muscle coordination, vision and hearing loss, and speech abnormalities. Treatment for Manken Disease is limited, but may include physical therapy, medications to control seizures, and supportive care. Genetic counseling can also be beneficial for those affected and their families.