ABSTRACT
BACKGROUND AND PURPOSE: ANRIL has long been considered as the strongest candidate gene at the 9p21 locus, robustly associated with stroke and coronary artery disease. However, the underlying molecular mechanism remains unknown. The present study works to elucidate such a mechanism. METHODS: Using expression quantitative loci analysis, we identified potential genes whose expression may be influenced by genetic variation in ANRIL. To verify the identified gene(s), knockdown and overexpression of ANRIL were evaluated in human umbilical vein endothelial cells and HepG2 cells. Ischemic stroke and coronary artery disease risk were then evaluated in the gene(s) demonstrated to be mediated by ANRIL in 3 populations of Chinese Han ancestry: 2 ischemic stroke populations consisting of the Central China cohort (903 cases and 873 controls) and the Northern China cohort (816 cases and 879 controls) and 1 coronary artery disease cohort consisting of 772 patients and 873 controls. RESULTS: Expression quantitative loci analysis identified CARD8 among others, with knockdown of ANRIL expression decreasing CARD8 expression and overexpression of ANRIL increasing CARD8 expression. The minor T allele of a previously identified CARD8 variant (rs2043211) was found to be significantly associated with a protective effect of ischemic stroke under the recessive model in 2 independent stroke cohorts. No significant association was found between rs2043211 and coronary artery disease. CONCLUSIONS: CARD8 is a downstream target gene regulated by ANRIL. Single nucleotide polymorphism rs2043211 in CARD8 is significantly associated with ischemic stroke. ANRIL may increase the risk of ischemic stroke through regulation of the CARD8 pathway.
Subject(s)
Brain Ischemia/genetics , CARD Signaling Adaptor Proteins/genetics , Neoplasm Proteins/genetics , RNA, Long Noncoding/genetics , Stroke/genetics , Adult , Aged , Aged, 80 and over , Asian People , Brain Ischemia/epidemiology , China/epidemiology , Coronary Artery Disease/epidemiology , Coronary Artery Disease/genetics , Female , Gene Expression/physiology , Genotype , Humans , Male , Middle Aged , Polymorphism, Single Nucleotide/genetics , Real-Time Polymerase Chain Reaction , Stroke/epidemiology , TransfectionABSTRACT
The interleukin 1 family plays an important role in the immune and inflammatory responses. Coronary artery disease (CAD) is a chronic inflammatory disease. However, the genetic association between IL-37, the seventh member of the IL-1 family, and CAD is unknown. Here we show that a single nucleotide polymorphism in the IL-37 gene (rs3811047) confers a significant risk of CAD. We have performed an association analysis between rs3811047 and CAD in two independent populations with 2,501 patients and 3,116 controls from China. Quantitative RT-PCR analysis has been performed to determine if the IL-37 expression level is influenced by rs3811047. We show that the minor allele A of rs3811047 is significantly associated with CAD in two independent populations under a recessive model (Padj = 5.51 × 10-3/OR = 1.56 in the GeneID Northernern population and Padj = 1.23 × 10-3/OR = 1.45 in the GeneID Central population). The association became more significant in the combined population (Padj = 9.70 × 10-6/OR = 1.47). Moreover, the association remains significant in a CAD case control population matched for age and sex. Allele A of rs3811047 shows significant association with a decreased mRNA expression level of IL-37 (n = 168, P = 3.78 × 10-4). These data suggest that IL37 is a new susceptibility gene for CAD, which provides a potential target for the prevention and treatment of CAD.