Liang Yulan, Kelemen Arpad
Department of Family and Community Health Department of Organizational Systems and Adult Health, University of Maryland, Baltimore, MD.
Medicine (Baltimore). 2017 Sep;96(37):e7683. doi: 10.1097/MD.0000000000007683.
Genetic and environmental (behavior, clinical, and demographic) factors are associated with increased risks of both myocardial infarction (MI) and high cholesterol (HC). It is known that HC is major risk factor that may cause MI. However, whether there are common single nucleotide polymorphism (SNPs) associated with both MI and HC is not firmly established, and whether there are modulate and modified effects (interactions of genetic and known environmental factors) on either HC or MI, and whether these joint effects improve the predictions of MI, is understudied.The purpose of this study is to identify novel shared SNPs and modifiable environmental factors on MI and HC. We assess whether SNPs from a metabolic pathway related to MI may relate to HC; whether there are moderate effects among SNPs, lifestyle (smoke and drinking), HC, and MI after controlling other factors [gender, body mass index (BMI), and hypertension (HTN)]; and evaluate prediction power of the joint and modulate genetic and environmental factors influencing the MI and HC.This is a retrospective study with residents of Erie and Niagara counties in New York with a history of MI or with no history of MI. The data set includes environmental variables (demographic, clinical, lifestyle). Thirty-one tagSNPs from a metabolic pathway related to MI are genotyped. Generalized linear models (GLMs) with imputation-based analysis are conducted for examining the common effects of tagSNPs and environmental exposures and their interactions on having a history of HC or MI.MI, BMI, and HTN are significant risk factors for HC. HC shows the strongest effect on risk of MI in addition to HTN; gender and smoking status while drinking status shows protective effect on MI. rs16944 (gene IL-1β) and rs17222772 (gene ALOX) increase the risks of HC, while rs17231896 (gene CETP) has protective effects on HC either with or without the clinical, behavioral, demographic factors with different effect sizes that may indicate the existence of moderate or modifiable effects. Further analysis with the inclusions of gene-gene and gene-environmental interactions shows interactions between rs17231896 (CETP) and rs17222772 (ALOX); rs17231896 (CETP) and gender. rs17237890 (CETP) and rs2070744 (NOS3) are found to be significantly associated with risks of MI adjusted by both SNPs and environmental factors. After multiple testing adjustments, these effects diminished as expected. In addition, an interaction between drinking and smoking status is significant. Overall, the prediction power in successfully classifying MI status is increased to 80% with inclusions of all significant tagSNPs and environmental factors and their interactions compared with environmental factors only (72%).Having a history of either HC or MI has significant effects on each other in both directions, in addition to HTN and gender. Genes/SNPs identified from this analysis that are associated with HC may be potentially linked to MI, which could be further examined and validated through haplotype-pairs analysis with appropriate population stratification corrections, and function/pathway regulation analysis to eliminate the limitations of the current analysis.
遗传因素和环境因素(行为、临床和人口统计学因素)与心肌梗死(MI)和高胆固醇(HC)风险增加相关。已知HC是可能导致MI的主要风险因素。然而,与MI和HC均相关的常见单核苷酸多态性(SNP)尚未完全明确,对于HC或MI是否存在调节和修饰作用(遗传因素与已知环境因素的相互作用),以及这些联合作用是否能改善MI的预测,目前研究较少。本研究的目的是识别MI和HC新的共享SNP以及可改变的环境因素。我们评估与MI相关代谢途径中的SNP是否与HC相关;在控制其他因素[性别、体重指数(BMI)和高血压(HTN)]后,SNP、生活方式(吸烟和饮酒)、HC和MI之间是否存在中度效应;并评估联合及调节遗传和环境因素对MI和HC的预测能力。
这是一项对纽约伊利县和尼亚加拉县有MI病史或无MI病史居民的回顾性研究。数据集包括环境变量(人口统计学、临床、生活方式)。对与MI相关代谢途径中的31个标签SNP进行基因分型。采用基于插补分析的广义线性模型(GLM),以检验标签SNP和环境暴露及其相互作用对有HC或MI病史的共同影响。
MI、BMI和HTN是HC的显著风险因素。除HTN外,HC对MI风险的影响最强;性别和吸烟状况有影响,而饮酒状况对MI有保护作用。rs16944(基因IL - 1β)和rs17222772(基因ALOX)增加HC风险,而rs17231896(基因CETP)无论有无临床、行为、人口统计学因素,对HC均有保护作用,不同的效应大小可能表明存在中度或可改变的效应。纳入基因 - 基因和基因 - 环境相互作用的进一步分析显示rs17231896(CETP)与rs17222772(ALOX)之间存在相互作用;rs17231896(CETP)与性别之间存在相互作用。发现rs17237890(CETP)和rs2070744(NOS3)在经SNP和环境因素调整后与MI风险显著相关。经过多重检验校正后,这些效应如预期般减弱。此外,饮酒和吸烟状况之间的相互作用显著。总体而言,与仅考虑环境因素相比(72%),纳入所有显著的标签SNP、环境因素及其相互作用后,成功分类MI状态的预测能力提高到了80%。
有HC或MI病史除了对HTN和性别有显著影响外,两者在两个方向上也相互有显著影响。从该分析中鉴定出的与HC相关的基因/SNP可能与MI潜在相关,可通过适当的人群分层校正的单倍型对分析以及功能/途径调节分析进一步检查和验证,以消除当前分析的局限性。