Gene variants at FTO, 9p21, and 2q36.3 are age-independently associated with myocardial infarction in Czech men

APOL1 polymorphisms are not influencing acute coronary syndrome risk in Czech males

BACKGROUND

The highest mortality and morbidity worldwide is associated with atherosclerotic cardiovascular disease (ASCVD), which has in background both environmental and genetic risk factors. Apolipoprotein L1 (APOL1) variability influences the risk of ASCVD in Africans, but little is known about the APOL1 and ASCVD in other ethnic groups.

METHODS

To investigate the role of APOL1 and ASCVD, we have genotyped four (rs13056427, rs136147, rs10854688 and rs9610473) APOL1 polymorphisms in a group of 1541 male patients with acute coronary syndrome (ACS) and 1338 male controls.

RESULTS

Individual APOL1 polymorphisms were not associated with traditional CVD risk factors such as smoking, hypertension or diabetes prevalence, with BMI values or plasma lipid levels. Neither individual polymorphisms nor haplotypes were associated with an increased risk of ACS nor did they predict total or cardiovascular mortality over the 10.2 ± 3.9 years of follow-up.

CONCLUSIONS

We conclude that APOL1 genetic variability has no major effect on risk of ACS in Caucasians.

Epitranscriptomic Regulations in the Heart

RNA modifications affect key stages of the RNA life cycle, including splicing, export, decay, and translation. Epitranscriptomic regulations therefore significantly influence cellular physiology and pathophysiology. Here, we selected some of the most abundant modifications and reviewed their roles in the heart and in cardiovascular diseases: N6-methyladenosine (m6A), N6,2'-O-dimethyladenosine (m6Am), N1-methyladenosine (m1A), pseudouridine (?), 5 methylcytidine (m5C), and inosine (I). Dysregulation of epitranscriptomic machinery affecting these modifications vastly changes the cardiac phenotype and is linked with many cardiovascular diseases such as myocardial infarction, cardiomyopathies, or heart failure. Thus, a deeper understanding of these epitranscriptomic changes and their regulatory mechanisms can enhance our knowledge of the molecular underpinnings of prevalent cardiac diseases, potentially paving the way for novel therapeutic strategies. Keywords: Epitranscriptomics, RNA modifications, Epigenetics, m6A, RNA, Heart.

Cholesterol associated genetic risk score and acute coronary syndrome in Czech males

BACKGROUND

Despite a general decline in mean levels across populations, LDL-cholesterol levels remain a major risk factor for acute coronary syndrome (ACS). The APOB, LDL-R, CILP, and SORT-1 genes have been shown to contain variants that have significant effects on plasma cholesterol levels.

METHODS AND RESULTS

We examined polymorphisms within these genes in 1191 controls and 929 patients with ACS. Only rs646776 within SORT-1 was significantly associated with a risk of ACS (P < 0.05, AA vs. + G comparison; OR 1.21; 95% CI 1.01-1.45). With regard to genetic risk score (GRS), the presence of at least 7 alleles associated with elevated cholesterol levels was connected with increased risk (P < 0.01) of ACS (OR 1.26; 95% CI 1.06-1.52). Neither total mortality nor CVD mortality in ACS subjects (follow up-9.84 ± 3.82 years) was associated with the SNPs analysed or cholesterol-associated GRS.

CONCLUSIONS

We conclude that, based on only a few potent SNPs known to affect plasma cholesterol, GRS has the potential to predict ACS risk, but not ACS associated mortality.

RNA modification m6Am: the role in cardiac biology

Epitranscriptomic modifications have recently emerged into the spotlight of researchers due to their vast regulatory effects on gene expression and thereby cellular physiology and pathophysiology. N⁶,2'-O-dimethyladenosine (m⁶Am) is one of the most prevalent chemical marks on RNA and is dynamically regulated by writers (PCIF1, METTL4) and erasers (FTO). The presence or absence of m⁶Am in RNA affects mRNA stability, regulates transcription, and modulates pre-mRNA splicing. Nevertheless, its functions in the heart are poorly known. This review summarizes the current knowledge and gaps about m⁶Am modification and its regulators in cardiac biology. It also points out technical challenges and lists the currently available techniques to measure m⁶Am. A better understanding of epitranscriptomic modifications is needed to improve our knowledge of the molecular regulations in the heart which may lead to novel cardioprotective strategies.

Emerging Role and Mechanism of the FTO Gene in Cardiovascular Diseases

The fat mass and obesity-associated (FTO) gene was the first obesity-susceptibility gene identified through a genome-wide association study (GWAS). A growing number of studies have suggested that genetic variants of FTO are strongly associated with the risk of cardiovascular diseases, including hypertension and acute coronary syndrome. In addition, FTO was also the first N⁶-methyladenosine (m6A) demethylase, suggesting the reversible nature of m6A modification. m6A is dynamically deposited, removed, and recognized by m6A methylases, demethylases, and m6A binding proteins, respectively. By catalyzing m6A demethylation on mRNA, FTO may participate in various biological processes by modulating RNA function. Recent studies demonstrated that FTO plays a pivotal role in the initiation and progression of cardiovascular diseases such as myocardial fibrosis, heart failure, and atherosclerosis and may hold promise as a potential therapeutic target for treating or preventing a variety of cardiovascular diseases. Here, we review the association between FTO genetic variants and cardiovascular disease risk, summarize the role of FTO as an m6A demethylase in cardiovascular disorders, and discuss future research directions and possible clinical implications.

A haemochromatosis-causing HFE mutation is associated with SARS-CoV-2 susceptibility in the Czech population

BACKGROUND

Coronavirus disease (COVID-19), which is caused by the SARS-CoV-2 virus, has become a global pandemic. While susceptibility to COVID-19 is subject to several external factors, including hypertension, BMI, and the presence of diabetes, it is also genetically determined to a significant extent. Infectious agents require iron (Fe) for proper functioning. Carriers of mutations resulting in increased iron concentrations are understood to be at increased risk of COVID-19.

METHODS

We examined HFE genotypes associated with hereditary haemochromatosis (rs1800562 and rs1799945 SNPs) in 617 COVID-19 patients (166 asymptomatic, 246 symptomatic and 205 hospitalised survivors) and 2 559 population-based controls.

RESULTS

We found a higher frequency of the minor allele (Tyr282) of the rs1800562 polymorphism (P < 0.002) in patients compared to controls (8.5 % vs 5.5 %). Non-carriers of the minor allele were protected against SARS-Cov-2 infection (OR, 95 %CI; 0.59, 0.42-0.82). The frequency of minor allele carriers was almost identical across asymptomatic, symptomatic, and hospitalised survivors. The rs1799945 variant did not affect disease severity and its occurrence was almost identical in patients and controls (P between 0.58 and 0.84).

CONCLUSIONS

In conclusion, our results indicate that presence of the rs1800562 minor allele, which is associated with hereditary haemochromatosis (thus increased levels of plasma Fe), increases susceptibility to SARS-CoV-2.

Increased prevalence of the CVD-associated ANRIL allele in the Roma/Gypsy population in comparison with the majority Czech population

Cardiovascular disease (CVD) is a major cause of death around the world, with highest prevalence reported in minority Roma/Gypsy populations living in developed countries. Whether these differences are caused by unhealthy lifestyles or genetic factors remain unknown. The aim of our study was to examine the genotype frequencies of the rs10757274 polymorphism in the 9p.21 locus within ANRIL (antisense non-coding RNA in the INK4 locus), a long non-coding RNA located in the vicinity of the CDKN2A/2B inhibitors loci. ANRIL is understood to be the strongest genetic determinant of CVD in Caucasians. Using PCR-RFLP, we analysed the ANRIL rs10757274 polymorphism in 298 non-Roma (50% male) and 302 Roma/Gypsy (50% male) adult (39.5 ± 15.1 years and 39.2 ± 12.8 years, respectively) subjects. We found that frequencies of the ANRIL GG, GA and AA genotypes were 20.1%, 52.4% and 27.5% in the majority population and 32.9%, 47.9% and 19.2% in Roma/Gypsy subjects, respectively. The distribution of genotypes was deemed significantly different at P < 0.001. Within the Roma/Gypsy population, we detected increased prevalence of the CVD-associated GG genotype. Increased prevalence of CVD among Roma/Gypsies subjects may be significantly linked to genetic background.

BMI-associated gene variants in FTO and cardiometabolic and brain disease: obesity or pleiotropy?

Obesity is a causal risk factor for the development of age-related disease conditions, which includes Type 2 diabetes mellitus, cardiovascular disease, and dementia. In genome-wide association studies, genetic variation in FTO is strongly associated with obesity and has been described across different ethnic backgrounds and life stages. To date, much work has been devoted on determining the biological mechanisms via which FTO affects body weight regulation and ultimately contributes to age-related cardiometabolic and brain disease. The main hypotheses of the involved biological mechanisms include the involvement of FTO in habitual food intake and energy expenditure. In this narrative review, our overall aim is to provide an overview on how FTO gene variants could increase the risk of developing age-related disease conditions. Specifically, we will discuss the state of the literature based on the different hypotheses how FTO regulates body weight and ultimately contributes to cardiometabolic disease and brain disease.

The association between the FTO gene variant and alcohol consumption and binge and problem drinking in different gene-environment background: The HAPIEE study

BACKGROUND

Alcohol intake and tobacco smoking have significant negative health consequences and both are influenced by genetic predispositions. Some studies suggest that the FTO gene is associated with alcohol consumption. We investigated whether a tagging variant (rs17817449) within the FTO gene is associated with alcohol intake, problem drinking and smoking behaviour.

METHODS

We analysed data from 26,792 Caucasian adults (47.2% of males; mean age 58.9 (±7.3) years), examined through the prospective cohort HAPIEE study. The primary outcomes were daily alcohol consumption, binge drinking, problem drinking (CAGE score 2+) and smoking status in relation to tagging variants within the FTO and ADH1B genes.

RESULTS

We found no significant association of the FTO polymorphism with smoking status in either sex. The associations of the FTO polymorphism with drinking pattern were inconsistent and differed by gender. In men, GG homozygote carriers had lower odds of problem drinking (OR 0.85, 95% CI 0.75-0.96, p = 0.03). In women, the combination of the FTO/ADH1B GG/+A genotypes doubled the risk of binge drinking (OR 2.10, 95% CI 1.19-3.71, p < 0.05), and the risk was further increased among smoking women (OR 4.10, 95% CI 1.64-10.24, p = 0.008).

CONCLUSIONS

In this large population study, the FTO gene appeared associated with binge and problem drinking, and the associations were modified by sex, smoking status and the ADH1B polymorphism.

KIF6 gene as a pharmacogenetic marker for lipid-lowering effect in statin treatment

INTRODUCTION

The therapeutic response to statins has a high interindividual variability with respect to reductions in plasma LDL-cholesterol (c-LDL) and increases in HDL cholesterol (c-HDL). Many studies suggest that there is a relationship between the rs20455 KIF6 gene variant (c.2155T> C, Trp719Arg) and a lower risk of cardiovascular disease in patients being treated with statins.

AIM

The aim of this study was to investigate whether or not the c.2155T> C KIF6 gene variant modulates the hypercholesteremic effects of treatment with simvastatin, atorvastatin, or rosuvastatin.

MATERIALS AND METHODS

This was a prospective, observational and multicenter study. Three hundred and forty-four patients who had not undergone prior lipid-lowering treatment were recruited. Simvastatin, atorvastatin or rosuvastatin were administered. Lipid profiles and multiple clinical and biochemical variables were assessed before and after treatment.

RESULTS

The c.2155T> C variant of the KIF6 gene was shown to influence physiological responses to treatment with simvastatin and atorvastatin. Patients who were homozygous for the c.2155T> C variant (CC genotype, ArgArg) had a 7.0% smaller reduction of LDL cholesterol levels (p = 0.015) in response to hypolipidemic treatment compared to patients with the TT (TrpTrp) or CT (TrpArg) genotype. After pharmacological treatment with rosuvastatin, patients carrying the genetic variant had an increase in c-HDL that was 21.9% lower compared to patients who did not carry the variant (p = 0.008).

CONCLUSION

Being a carrier of the c.2155T> C variant of the KIF6 gene negatively impacts patient responses to simvastatin, atorvastatin or rosuvastatin in terms of lipid lowering effect. Increasing the intensity of hypolipidemic therapy may be advisable for patients who are positive for the c.2155T> C variant.

Association between KIF6 rs20455 polymorphism and the risk of coronary heart disease (CHD): a pooled analysis of 50 individual studies including 40,059 cases and 64,032 controls

Background

The KIF6 rs20455 polymorphism has been verified as an important genetic factor of coronary heart disease (CHD), but with controversial results. The aim of this study was to explore the association between KIF6 rs20455 polymorphism and susceptibility to CHD.

Methods

All eligible studies were identified by searching Medline (mainly PubMed), EMBASE, the Web of Science, Cochrane Collaboration Database, Chinese National Knowledge Infrastructure, Wanfang Database and China Biological Medicine up to October 5, 2016.Odds ratios (ORs) with 95% confidence interval (CI) were used to explore the association between KIF6 rs20455 polymorphism and CHD risk. Begg’s and Egger’s tests were used to examine the publication bias. Subgroup analysis and sensitivity analysis were performed to test the reliability and stability of the results. All the analyses were carried out by Stata 12.0 software.

Results

A total of 28 publications including 50 individual studies were analyzed in this present work. There are no significant association found between KIF6 rs20455 polymorphism and CHD risk (Homozygote model: OR = 1.007, 95% CI =0.952–1.066, P = 0.801; Heterozygote model: OR = 1.009, 95% CI = 0.968–1.052, P = 0.636; Dominant model: OR = 1.007, 95% CI = 0.966–1.048, P = 0.753; Recessive model: OR = 0.989, 95% CI = 0.943–1.037, P = 0.655; Allele comparison model: OR = 1.00, 95% CI = 0.971–1.030, P = 0.988). Furthermore, subgroup analyses were performed by ethnicity, source of control.

Conclusions

Our result suggests that KIF6 rs20455 polymorphism may not be associated with CHD susceptibility. However, additional very well-designed large-scale studies are warranted to confirm our results.

The FTO variant is associated with chronic complications of diabetes mellitus in Czech population

BACKGROUND

Genome-wide association studies have resulted in the identification of the FTO gene as an important genetic determinant of diabetes mellitus. The aim of this study was to confirm the role of this gene in the development of DM in the Czech-Slavonic population and to analyse whether this gene is associated with common DM complications.

METHODS

Two groups of patients (814 with T1DM and 848 with T2DM) and a group of healthy controls (2339 individuals) - both of Czech origin - were genotyped for the FTO rs17817449 SNP. ANOVA and logistic regression were used for the statistical evaluations.

RESULTS

The frequency of the GG genotype was significantly higher in T2DM (25.4% vs. 16.7%, P<0.0005) but not in T1DM patients (19.3% vs. 16.7%, P=0.20) than in controls. The increased risk of development of diabetic nephropathy was observed both for T1DM patients (GG vs. TT homozygotes, P<0.01) and T2DM patients (G carriers vs. TT homozygotes, P<0.05). FTO genotype predicted the development of diabetic neuropathy (GG vs. TT comparison; P<0.01) in the T2DM patients only. No association between FTO genotype and development of retinopathy was detected. All presented values are after adjustment for age, sex, BMI and duration of diabetes.

CONCLUSIONS

We confirm the association between the FTO rs17817449 SNP and susceptibility to T2DM in the Czech-Slavonic population. The same variant is associated with a spectrum of chronic complications in both types of diabetes.

Translating the biology of adipokines in atherosclerosis and cardiovascular diseases: Gaps and open questions

AIM

Critically discuss the available data, to identify the current gaps and to provide key concepts that will help clinicians in translating the biology of adipokines in the context of atherosclerosis and cardio-metabolic diseases.

DATA SYNTHESIS

Adipose tissue is nowadays recognized as an active endocrine organ, a function related to the ability to secrete adipokines (such as leptin and adiponectin) and pro-inflammatory cytokines (tumor necrosis factor alpha and resistin). Studies in vitro and in animal models have observed that obesity status presents a chronic low-grade inflammation as the consequence of the immune cells infiltrating the adipose tissue as well as adipocytes. This inflammatory signature is often related to the presence of cardiovascular diseases, including atherosclerosis and thrombosis. These links are less clear in humans, where the role of adipokines as prognostic marker and/or player in cardiovascular diseases is not as clear as that observed in experimental models. Moreover, plasma adipokine levels might reflect a condition of adipokine-resistance in which adipokine redundancy occurs. The investigation of the cardio-metabolic phenotype of carriers of single nucleotide polymorphisms affecting the levels or function of a specific adipokine might help determine their relevance in humans. Thus, the aim of the present review is to critically discuss the available data, identify the current gaps and provide key concepts that will help clinicians translate the biology of adipokines in the context of atherosclerosis and cardio-metabolic diseases.

Polygenic Hypercholesterolemia: Examples of GWAS Results and Their Replication in the Czech-Slavonic Population

Since 2007, the year of their first widespread use, genome-wide association studies (GWAS) have become the “gold standard” for the detection of causal genes and polymorphisms in all fields of human medicine. Cardiovascular disease (CVD), one of the major causes of morbidity and mortality, is no exception. The first GWAS focused on hypercholesterolemia and dyslipidemia as the major CVD determinants. GWAS confirm the importance of most of the previously identified genes (e.g. APOE, APOB, LDL-R) and recognize the importance of new genetic determinants (e.g. within the CILP2 or SORT1 gene clusters). Nevertheless, the results of GWAS still require confirmation by independent studies, as interethnic and interpopulation variability of SNP effects have been reported. We analyzed an association between eight variants within seven through GWAs detected loci and plasma lipid values in the Czech post-MONICA population sample (N=2,559). We confirmed an association (all P<0.01) between plasma LDL-cholesterol values and variants within the CILP2 (rs16996148), SORT1 (rs646776), APOB (rs693), APOE (rs4420638) and LDL-R (rs6511720) genes in both males (N=1,194) and females (N=1,368). In contrast, variants within the APOB (rs515135), PCSK9 (rs11206510) and HMGCoAR (rs12654264) genes did not significantly affect plasma lipid values in Czech males or females. Unweighted gene score values were linearly associated with LDL-cholesterol values both in males (P<0.0005) and females (P<0.00005). We confirmed the effects of some, but not all analyzed SNPs on LDL-cholesterol levels, reinforcing the necessity for replication studies of GWA-detected gene variants.

Traditional Risk Factors of Acute Coronary Syndrome in Four Different Male Populations – Total Cholesterol Value Does Not Seem To Be Relevant Risk Factor

Cardiovascular diseases are the most common cause of mortality and morbidity in most populations. As the traditional modifiable risk factors (smoking, hypertension, dyslipidemia, diabetes mellitus, and obesity) were defined decades ago, we decided to analyze recent data in patients who survived acute coronary syndrome (ACS). The Czech part of the study included data from 999 males, and compared them with the post-MONICA study (1,259 males, representing general population). The Lithuanian study included 479 male patients and 456 age-matched controls. The Kazakhstan part included 232 patients and 413 controls. In two countries, the most robust ACS risk factor was smoking (OR 3.85 in the Czech study and 5.76 in the Lithuanian study), followed by diabetes (OR 2.26 and 2.07) and hypertension (moderate risk elevation with OR 1.43 and 1.49). These factors did not influence the ACS risk in Kazakhstan. BMI had no significant effect on ACS and plasma cholesterol was surprisingly significantly lower (P<0.001) in patients than in controls in all countries (4.80±1.11 vs. 5.76±1.06 mmol/l in Czechs; 5.32±1.32 vs. 5.71±1.08 mmol/l in Lithuanians; 4.88±1.05 vs. 5.38±1.13 mmol/l in Kazakhs/Russians). Results from our study indicate substantial heterogeneity regarding major CVD risk factors in different populations with the exception of plasma total cholesterol which was inversely associated with ACS risk in all involved groups. These data reflect ethnical and geographical differences as well as changing pattern of cardiovascular risk profiles.