ceroid lipofuscinosis, neuronal, 6A (Monarch Disease Ontology id MONDO_0011144) is a rare condition that affects the nervous system. Signs and symptoms of the condition generally develop between ages 18 months and 8 years, although later onset cases have been reported. Affected people may experience loss of muscle coordination (ataxia), seizures that do not respond to medications, muscle twitches (myoclonus), visual impairment, and developmental regression (loss of previously acquired skills). It occurs predominantly in people of Portuguese, Indian, Pakistani, or Czech ancestry. CLN6-NCL is caused by changes (mutations) in the CLN6 gene and is inherited in an autosomal recessive manner. Treatment options are limited to therapies that can help relieve some of the symptoms. Also known as: CLN6, CLN6 late infantile neuronal ceroid lipofuscinosis, CLN6A, ceroid lipofuscinosis, neuronal, type 6, late infantile neuronal ceroid lipofuscinosis caused by mutation in CLN6, neuronal ceroid lipofuscinosis 6, neuronal ceroid lipofuscinosis 6 variable age of onset, neuronal ceroid lipofuscinosis type 6.