The protein encoded by this gene is a tetrahydrobiopterin- and iron-dependent enzyme that cleaves the ether bond of alkylglycerols. Sequence comparisons distinguish this protein as forming a third, distinct class of tetrahydrobiopterin-dependent enzymes. Variations in this gene have been associated with decreased glucose-stimulated insulin response, type 2 diabetes, and susceptibility to intracranial aneurysms. [provided by RefSeq, Aug 2012]