Common variants in the haemostatic gene pathway contribute to risk of early-onset myocardial infarction in the Italian population
THROMBOSIS AND HAEMOSTASIS
Authors: Guella, Ilaria; Duga, Stefano; Ardissino, Diego; Merlini, Pier Angelica; Peyvandi, Flora; Mannucci, Pier Mannuccio; Asselta, Rosanna
Abstract
Occlusive coronary thrombus formation superimposed on an atherosclerotic plaque is the ultimate event leading to myocardial infarction (MI). Therefore, haemostatic proteins may represent important players in the pathogenesis of MI. It was the objective of this study to evaluate, in a comprehensive way, the role of haemostatic gene polymorphisms in predisposition to premature MI. A total of 810 single nucleotide polymorphisms (SNPs) in 37 genes were assessed for association with MI in a large cohort (1,670 males, 210 females) of Italian patients who suffered from an MI event before the age of 45, and an equal number of controls. Thirly-eight SNPs selected from the literature were genotyped using the SNPlex technology, whereas genotypes for the remaining 772 SNPs were extracted from a previous genome-wide association study. Genotypes were analysed by a standard case-control analysis corrected for classical cardiovascular risk factors, and by haplotype analysis. A weighted Genetic Risk Score (GRS) was calculated. Evidence for association with MI after covariate correction was found for 35 SNPs in 12 loci: F5, PROS1, F11, ITGA2, F12, F13A1, SERPINE1, PLAT, VWF, THBD, PROCR, and F9. The weighted GRS was constructed by including the top SNP for each of the 12 associated loci. The GRS distribution was significantly different between cases and controls, and subjects in the highest quintile had a 2.69-fold increased risk for MI compared with those in the lowest quintile. Our results suggest that a GRS, based on the combined effect of several risk alleles in different haemostatic genes, is associated with an increased risk of MI.
THE HUMAN ENDOTHELIN-1 GENE (EDN1) ENCODING A PEPTIDE WITH POTENT VASOACTIVE PROPERTIES MAPS DISTAL TO HLA ON CHROMOSOME ARM 6P IN CLOSE LINKAGE TO D6S89
CYTOGENETICS AND CELL GENETICS
Authors: HOEHE, MR; EHRENREICH, H; OTTERUD, B; CAENAZZO, L; PLAETKE, R; ZANDER, H; LEPPERT, M
Abstract
We determined the precise genetic location of the human endothelin-1 gene (EDN1), which encodes a peptide with extremely potent vasoactive properties and is apparently involved in a spectrum of diseases ranging from hypertension to asthma. Analyzing the segregation of a four-allele EDN1 polymorphism in 40 CEPH families including 480 individuals, we detected significant linkage of EDN1 to DNA markers spanning the telomeric half of chromosome arm 6p. EDN1 was closest to the highly polymorphic nucleotide-repeat marker D6S89 at a theta = 0.06 with the highest pairwise LOD score Z(max) = 31.2. Subsequent multipoint analysis placed EDN1 at 8 cM distal to D6S89; EDN1 was flanked at its telomeric site at a 13-cM distance by the gene encoding the A subunit of blood clotting factor XIII (F13A1). Furthermore, EDN1 was located at approximately 34-36 cM distal to the HLA region defined by HLA-A, -B, and -DRB1, and 31 cM proximal to the most telomeric marker D6S7. This location of EDN1 on the primary genetic map is strongly supported with odds of 2.7 x 10(12):1 against the next best alternative.