This gene encodes a member of the carboxylesterase large family. The family members are responsible for the hydrolysis or transesterification of various xenobiotics, such as cocaine and heroin, and endogenous substrates with ester, thioester, or amide bonds. They also participate in fatty acyl and cholesterol ester metabolism, and may play a role in the blood-brain barrier system. This gene, also called CES6, encodes a secreted enzyme, and may play a role in the detoxification of drugs and xenobiotics in neural and other tissues of the body and in the cerebrospinal fluid. Multiple transcript variants encoding different isoforms have been reported, but the full-length nature and/or biological validity of some variants have not been determined. [provided by RefSeq, Jun 2010]