PON1 and meningioma: To establish whether PON1 genotype and allelic variants could be related to the risk of developing brain astrocytoma and/or meningioma, we have compared the prevalence of the PON1-L55M and PON1- Q192R polymorphisms in the PON1 gene, in a group of 71 patients with these brain tumors (43 with astrocytoma grade II/III and 28 with meningioma), and 220 healty controls.