cells Article The rs508487, rs236911, and rs236918 Genetic Variants of the Proprotein Convertase Subtilisin–Kexin Type 7 (PCSK7) Gene Are Associated with Acute Coronary Syndrome and with Plasma Concentrations of HDL-Cholesterol and Triglycerides Gilberto Vargas-Alarcón 1,† , Oscar Pérez-Méndez 1,2,† ,Héctor González-Pacheco 3 , Julián Ramírez-Bello 4 , Rosalinda Posadas-Sánchez 5 , Galileo Escobedo 6 and José Manuel Fragoso 1,* 1 Department of Molecular Biology, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico; [email protected] (G.V.-A.); [email protected] (O.P.-M.) 2 School of Engineering and Sciences Campus CDMX, Tecnológico de Monterrey, Mexico City 14380, Mexico 3 Coronary Care Unit, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico; [email protected] 4 Research Unit, Hospital Juárez de México, Mexico City 01460, Mexico; [email protected] 5 Department of Endocrinology, Instituto Nacional de Cardiología Ignacio Chávez, Mexico City 14080, Mexico; [email protected] 6 Unit of the Experimental Medicine, Hospital General de México, Dr. Eduardo Liceaga, Citation: Vargas-Alarcón, G.; Mexico City 06726, Mexico; [email protected] Pérez-Méndez, O.; González-Pacheco, * Correspondence: [email protected]; Tel.: +52-55-5573-2911 (ext. 26302); Fax: +52-55-5573-0926 H.; Ramírez-Bello, J.; Posadas- † The contributions by G. Vargas-Alarcón and O. Pérez-Méndez are equal and the order of authorship Sánchez, R.; Escobedo, G.; Fragoso, is arbitrary. J.M. The rs508487, rs236911, and rs236918 Genetic Variants of the Abstract: Dyslipidemia has a substantial role in the development of acute coronary syndrome (ACS). Proprotein Convertase Subtilisin– Previous reports, including genome-wide associations studies (GWAS), have shown that some genetic Kexin Type 7 (PCSK7) Gene Are variants of the proprotein convertase subtilisin–kexin type 7 (PCSK7) gene are associated with plasma Associated with Acute Coronary lipid levels. In the present study, we evaluated whether PCSK7 gene polymorphisms are significantly Syndrome and with Plasma associated with the plasma lipid profile and ACS. Three PCSK7 gene polymorphisms (rs508487 Concentrations of HDL-Cholesterol T/C, rs236911 C/A, and rs236918 C/G) were determined using TaqMan genotyping assays in a and Triglycerides. Cells 2021, 10, 1444. https://doi.org/10.3390/ group of 603 ACS patients and 622 healthy controls. The plasma lipid profile was determined in cells10061444 the study groups by enzymatic/colorimetric assays. Under the recessive model, the rs236918 C allele was associated with a high risk of ACS (OR = 2.11, pC = 0.039). In the same way, under the Academic Editor: Sanjay Patel recessive and additive models, the rs236911 C allele was associated with a high risk of ACS (OR = 1.95, pC = 0.037, and OR = 1.28, pC = 0.037, respectively). In addition, under the co-dominant model, the Received: 27 April 2021 rs508487 T allele was associated with a higher risk of ACS (OR = 1.78, pC = 0.010). The CCC and TCC Accepted: 5 June 2021 haplotypes were associated with a high risk of ACS (OR = 1.21, pC = 0.047, and OR = 1.80, pC = 0.001, Published: 9 June 2021 respectively). The rs236911 CC and rs236918 CC genotypes were associated with lower high-density lipoproteins-cholesterol (HDL-C) plasma concentrations, whereas the rs236911 CC genotype was Publisher’s Note: MDPI stays neutral associated with a higher concentration of triglycerides, as demonstrated in the control individuals with regard to jurisdictional claims in who were not receiving antidyslipidemic drugs. Our data suggest that the PCSK7 rs508487 T/C, published maps and institutional affil- rs236911 C/A, and rs236918 C/G polymorphisms are associated with the risk of developing ACS, iations. and with plasma concentrations of HDL-C and triglycerides. Keywords: genetics; susceptibility; acute coronary syndrome; proprotein convertase subtilisin–kexin type 7 Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article 1. Introduction distributed under the terms and conditions of the Creative Commons ACS is a complex multifactorial disorder resulting from genetics and various envi- Attribution (CC BY) license (https:// ronmental factors, coupled with dyslipidemias, hypertension, diabetes, obesity, and a creativecommons.org/licenses/by/ smoking habit—factors that play a fundamental role in the development and progres- 4.0/). sion of atherosclerosis [1–3]. Dyslipidemias are considered one of the most important Cells 2021, 10, 1444. https://doi.org/10.3390/cells10061444 https://www.mdpi.com/journal/cells Cells 2021, 10, 1444 2 of 11 risk factors for acute coronary syndrome (ACS) and remain the primary target of current cardiovascular risk reduction strategies [2–4]. The proprotein convertase subtilisin–kexin type 7 (PCSK7) is a member of the propro- tein convertases family. These proprotein convertases are related to the cleavage peptide bonds of various proteins and peptides in multiple subcellular compartments included in the secretory pathway [endoplasmic reticulum (ER), various Golgi cisternae, endosomes], which leads to the activation/inactivation of receptors, ligands, enzymes, viral glycopro- teins, or growth factors [5]. Recent studies have shown that the human PCSK7 proprotein is implicated in the regulation of apolipoprotein A-5 (apoA-5) and is associated with a higher triglyceride concentration [6,7], both with an important role in the development of cardiovascular diseases [3,8–10]. The PCSK7 proprotein is encoded by the PCSK7 gene, located in the q23.3 region of chromosome 11. Genome-wide association studies (GWAS) have shown that some single nucleotide polymorphisms (SNPs) of the PCSK7 gene are associated with hypertriglyceridemia, with large effects on HDL-C and/or triglyceride lev- els [10–13]. Recent studies have associated three novel SNPs [PCSK7 nearGene-3 rs508487 T/C, PCSK7 intron 6 rs236911 C/A, and PCSK7 intron 9 rs236918 C/G] with an over- expression of the PCSK7 and hypertriglyceridemia [6,10–13], as well as with the risk of developing atherosclerosis and liver disease [4,10]. In this context, considering the important role of the PCSK7 protein in the regula- tion of the Apo-A5 as well as its association with triglyceride levels, the present study aimed to establish the association of the PCSK7 rs508487 T/C, rs236911 C/A, and rs236918 C/G polymorphisms with the susceptibility to developing ACS. Moreover, we evaluated whether these polymorphisms were associated with lipid profile plasma concentrations in a Mexican population sample. 2. Materials and Methods 2.1. Characteristics of the Study Population The sample size for the unmatched case-control study was calculated with a power of 80% and an alpha error of 0.05. The total sample size required to carry out this study was 528 Mexican mestizo individuals (264 patients with ACS and 264 control individuals) (http://www.openepi.com/SampleSize/SSCC.html (accessed on 5 February 2020)). This study included 1225 Mexican mestizos—603 patients with ACS and 622 healthy controls. From July 2010 to 2015, 603 patients with ACS (82% men and 18% women, with a mean age of 58 ± 10.5 years) were referred to the Instituto Nacional de Cardiologia Ignacio Chavez. The diagnosis of ACS was made based on clinical characteristics, electrocardiographic changes, and biochemical markers of cardiac necrosis (creatinine kinase isoenzymes, cre- atinine phosphokinase, or troponin I above the upper limit of normal); the European Society of Cardiology (ESC) and American College of Cardiology (ACC) definitions were followed [14,15]. The control group included 622 healthy individuals (69% men and 31% women, with a mean age of 54.0 ± 7.7 years) that were recruited from the database co- hort of the Genetics of Atherosclerosis Disease (GEA) Mexican study. The GEA study investigated the genetic factors associated with premature coronary artery disease (CAD), atherosclerosis, and other coronary risk factors in the Mexican population [16]. All subjects were asymptomatic and apparently healthy, without a family history of premature CAD or atherosclerosis; they were recruited from June 2009 to June 2013 from blood bank donors and with the assistance of brochures posted in social service centers. The exclusion criteria included congestive heart failure and liver, renal, thyroid, or oncological disease. Likewise, the control subjects had a coronary calcium score of “0” determined by computed tomog- raphy, indicating the absence of subclinical atherosclerosis in these individuals [16]. The contribution of the PCSK7 rs508487 T/C, rs236911 C/A, and rs236918 C/G SNP genotypes on the lipid plasma levels was evaluated only in a subset of healthy controls. All the included subjects were ethnically matched and considered Mexican mestizos only if they and their ancestors (at last three generations) had been born in the country. The study complies with the Declaration of Helsinki and was approved by the Ethics and Research Cells 2021, 10, 1444 3 of 11 commission of Instituto Nacional de Cardiologia Ignacio Chavez. Written informed consent was obtained from all individuals enrolled in the study. 2.2. Laboratory Analyses Cholesterol and triglyceride plasma concentrations were determined by enzy- matic/colorimetric assays (Randox Laboratories Crumlin, County Antrim, UK). HDL- cholesterol (C) concentrations were determined after precipitation of the apo B-containing lipoproteins by the phosphotungstic acid-Mg2+