The amount of a ubiquitin-conjugating enzyme E2 D4 (human) when measured in cerebrospinal fluid. The trait is Ontology of Biological Attributes identifier OBA_2081763 (level of ubiquitin-conjugating enzyme E2 D4 (human) in cerebrospinal fluid). Also known as: cerebrospinal fluid ubiquitin-conjugating enzyme E2 D4 (human) amount.