TLC (TRAM-LAG1-CLN8) (PS50922) is a member of a family of membrane-associated proteins that are associated with yeast LAG1 and mammals. Humans with CLN8 deficiency suffer from progressive epilepsy with mental retardation (EPMR), also known as neuronal ceroid lipofuscinosis (NCL) type 8 and northern epilepsy. In rodents, CLN8 deficiency is the cause of phenotypic motor neuron degeneration (MND), a naturally occurring NCL.