目的:中风是成人发病致残的主要原因。虽然临床因素影响卒中结局,个体之间存在显著的变异性,这可能归因于遗传学和表观遗传学,包括DNA甲基化(DNAm)。我们旨在研究DNAm与卒中预后之间的关联。
结果:为此,我们从两个独立的中心(BasicMar[发现,N=316]和St.Pau[复制,N=92])。卒中后三个月使用改良的Rankin量表(mRS)评估功能结局,不良结果定义为mRS>2。在前24小时内收集的全血样品中使用450K和EPICBeadChips确定DNAm。我们搜索了370,344CpG中的差异甲基化位置(DMPs),随后在复制队列中测试低于p值<10-5的候选者。然后,我们对两个队列的DMP结果进行了荟萃分析,并使用它们来鉴定差异甲基化区域(DMRs)。在进行了全表观基因组关联研究后,我们发现29个p值<10-5的DMPs,其中一个被复制:cg24391982,注释血小板反应蛋白2(THBS2)基因(p值发现=1.54·10-6;p值复制=9.17·10-4;p值分析=6.39·10-9).此外,在预后不良的患者中鉴定出四个DMRs,注释为锌指蛋白57同源物(ZFP57),花生四烯酸12-脂氧合酶12S型(ALOX12),ABI家族成员3(ABI3)和尿囊酶(ALLC)基因(所有情况下p值<1·10-9)。
结论:预后不良的患者在THBS2处显示DMP,并在ZFP57,ALOX12,ABI3和ALLC基因上注释了四个DMR。这表明卒中结果与DNAm之间存在关联,这可能有助于确定新的中风恢复机制。
OBJECTIVE: Stroke is the leading cause of adult-onset disability. Although clinical factors influence stroke outcome, there is a significant variability among individuals that may be attributed to genetics and epigenetics, including DNA methylation (DNAm). We aimed to
study the association between DNAm and stroke prognosis.
RESULTS: To that aim, we conducted a two-phase
study (discovery-replication and meta-analysis) in Caucasian patients with ischemic stroke from two independent centers (BasicMar [discovery, N = 316] and St. Pau [replication, N = 92]). Functional outcome was assessed using the modified Rankin Scale (mRS) at three months after stroke, being poor outcome defined as mRS > 2. DNAm was determined using the 450K and EPIC BeadChips in whole-blood samples collected within the first 24 h. We searched for differentially methylated positions (DMPs) in 370,344 CpGs, and candidates below p-value < 10-5 were subsequently tested in the replication cohort. We then meta-analyzed DMP results from both cohorts and used them to identify differentially methylated regions (DMRs). After doing the epigenome-wide association
study, we found 29 DMPs at p-value < 10-5 and one of them was replicated: cg24391982, annotated to thrombospondin-2 (THBS2) gene (p-valuediscovery = 1.54·10-6; p-valuereplication = 9.17·10-4; p-valuemeta-analysis = 6.39·10-9). Besides, four DMRs were identified in patients with poor outcome annotated to zinc finger protein 57 homolog (ZFP57), Arachidonate 12-Lipoxygenase 12S Type (ALOX12), ABI Family Member 3 (ABI3) and Allantoicase (ALLC) genes (p-value < 1·10-9 in all cases).
CONCLUSIONS: Patients with poor outcome showed a DMP at THBS2 and four DMRs annotated to ZFP57, ALOX12, ABI3 and ALLC genes. This suggests an association between stroke outcome and DNAm, which may help identify new stroke recovery mechanisms.