The amount of a ubiquitin carboxyl-terminal hydrolase isozyme L1 (human) when measured in cerebrospinal fluid. The trait is level of ubiquitin carboxyl-terminal hydrolase isozyme L1 (human) in cerebrospinal fluid (OBA_2056968). Also known as: cerebrospinal fluid ubiquitin carboxyl-terminal hydrolase isozyme L1 (human) amount.