Promoter Polymorphisms in the Plasma Glutathione Peroxidase ( GPx-3 ) Gene

Abstract
Background and Purpose— Plasma glutathione peroxidase (GPx-3)–deficiency increases extracellular oxidant stress, decreases bioavailable nitric oxide, and promotes platelet activation. The aim of this study is to identify polymorphisms in the GPx-3 gene, examine their relationship to arterial ischemic stroke (AIS) in a large series of children and young adults, and determine their functional molecular consequences. Methods— We studied the GPx-3 gene promoter from 123 young adults with idiopathic AIS and 123 age- and gender-matched controls by single-stranded conformational polymorphism and sequencing analysis. A second, independent population with childhood stroke was used for a replication study. We identified 8 novel, strongly linked polymorphisms in the GPx-3 gene promoter that formed 2 main haplotypes (H1 and H2). The transcriptional activity of the 2 most prevalent haplotypes was studied with luciferase reporter gene constructs. Results— The H2 haplotype was over-represented in both patient population...