CCR5Delta32 deletion as a protective factor in Czech first-wave COVID-19 subjects.

Infection by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease (COVID-19), has spread widely around the globe. Significant inter-individual differences have been observed during the course of the infection, which suggests that genetic susceptibility may be a contributing factor. CC chemokine receptor 5 (CCR5), which acts as a co-receptor for the entry of HIV-1 into cells, is promising candidate whose can have an influence on SARS-CoV-2 infection. A genetic mutation known as CCR5Delta32, consisting of a 32-nucleotide deletion, encodes a truncated protein that protects homozygous carriers of the deletion from HIV-1 infection. Similarly, inhibition of CCR5 seems to be protective against COVID-19. In our study, we successfully genotyped 416 first-wave SARS-CoV-2-positive infection survivors (164 asymptomatic and 252 symptomatic) for CCR5?32, comparing them with a population based sample of 2,404 subjects. We found the highest number (P=0.03) of CCR5Delta32 carriers in SARS-CoV-2-positive/COVID-19-asympto-matic subjects (23.8 %) and the lowest number in SARS-CoV-2-positive/COVID-19-symptomatic patients (16.7 %), with frequency in the control population in the middle (21.0 %). We conclude that the CCR5?32 I/D polymorphism may have the potential to predict the severity of SARS-CoV-2 infection.

Prediction of long-term prognosis of age-related macular degeneration treated by hemorheologic therapy using baseline laboratory indicators - Experimental-clinical model.

BACKGROUND + OBJECTIVE:Age-related macular degeneration (AMD) is the most common cause of practical blindness in people over 60 years of age in industrialised countries. We formulated a hypothesis that a group of initial laboratory parameters would be suitable for prediction of prognosis of AMD, allowing for individual modifications in treatment intensity. PATIENTS AND METHODS: 66 patients with dry form of AMD were treated using rheohaemapheresis with an individual follow-up period of more than 5 years. The patients' initial laboratory data was split in two subgroups based on treatment success and analysed using discriminant analysis (analysis of the linear and quadratic models using the automated and interactive step-wise approach) by means of the Systat 13 software. RESULTS: Prediction of prognosis based on the initial laboratory parameters was correct in 79% of unsuccessfully treated patients, allowing for early detection of high-risk patients. With the use of a quadratic model, the prediction was correct in 100% of unsuccessfully treated patients and in 75% of successfully treated patients. CONCLUSION: Implementation of discriminant analysis is a promising method for prediction of prognosis, especially when the patient is at risk of AMD progression, which allows for early and more intensive monitoring and treatment.

Strong Association between APOA5 Gene Polymorphisms and Hypertriglyceridaemic Episodes.

Plasma triglyceride (TG) levels represent a significant risk factor of cardiovascular and total mortality. Concentrations of TG in the plasma depend, to a large extent, on the genetic background, and the apolipoprotein A5 (APOA5) gene seems to be one of the most powerful players in the plasma TG metabolism regulation. In total, we analysed three tagging APOA5 (rs964184 rs662799, rs3135506) SNPs in 209 patients with plasma TG levels over 10 mmol/l (HTG) on at least one occasion and in 379 treatment-naïve controls (NTG) with plasma TG values within the normal range. Minor alleles of all three analysed APOA5 polymorphisms significantly (all P < 0.0001) increased the risk of hypertriglyceridaemia. The most significant association (P < 0.0000001) was observed for the rs964184 polymorphism, where the minor GG homozygotes had the odds ratio (OR, 95% CI) for hypertriglyceridaemia development 21.30 (8.09-56.07, P < 0.000001) in comparison with the major CC allele homozygotes. Carriers of at least one minor allele at rs3135506 had OR (95% CI) 4.19 (2.75-6.40); (P < 0.000005) for HTG development and similarly, carriers of a minor allele at rs662799 had OR (95% CI) 3.07 (2.00-4.72) (P < 0.0001). The cumulative presence of risk alleles (unweighted gene score) significantly differed between patients with episodes of high TG and controls at P < 0.0000001. There were 73 % of subjects without any of the risk alleles among the controls and 46 % in the patients. In contrast, the controls just included 3 % of subjects with score 3 and more in comparison with 18 % in HTG patients. We conclude that common APOA5 variants are very important genetic determinants of episodic hypertriglyceridaemia in the Czech population with a high potential to be applied in personalized medicine.

Regulatory RNAs and cardiovascular disease - with a special focus on circulating microRNAs.

MicroRNAs (miRNAs) are a class of short non-coding regulatory RNA molecules which play an important role in intracellular communication and cell signaling and which influence cellular processes such as proliferation, differentiation, and cellular death. Over the past two decades, the crucial role of microRNAs in controlling tissue homeostasis and disease in cardiovascular systems has become widely recognized. By controlling the expression levels of their targets, several miRNAs have been shown to modulate the function of endothelial cells (miR-221/222 and -126), vascular smooth muscle cells (miR-143/145) and macrophages (miR-33, -758, and -26), thereby regulating the development and progression of atherosclerosis. The stability of miRNAs within the blood suggests that circulating miRNAs may function as important biomarkers of disease development and progression. Numerous circulating miRNAs have been found to be dysregulated in a wide variety of different disease states, including diabetes, cancer, and cardiovascular disease.

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.

Can Leukocyte Telomere Length Predict Survival Time in Heart Transplant Recipients over a Minimal Follow-Up of 20 years?

In humans, leukocyte telomere length (LTL) reduces with age and is reported to be inversely associated with ageing-related diseases. We measured LTL in leukocyte DNA using a quantitative PCR-based method from 127 blood samples of heart recipients (107 males, 20 females, age 44.1 ± 10.5), followed for up to 30 years. Patients with coronary artery disease survived for a shorter time and also had shorter LTL (both P < 0.05 after adjustment for age and sex) than subjects with dilated cardiomyopathy. Patients with non-cardiac causes of death had shorter LTL than patients with cardiac causes (P < 0.05 after adjustment for age). An inverse correlation between LTL and age (P < 0.03) was observed in patients with non-cardiac causes of death only. Most importantly, LTL was not associated with general survival time in patients after heart transplantation. However, shorter LTL was a marker of non-cardiac causes of death. Different LTLs and survival times were determined in association with aetiology of heart failure (HF).

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

AIM: Cardiovascular disease (CVD) is a major cause of morbidity and mortality in developed countries. This study aimed to confirm the effect of common putative CVD-associated gene variants (FTO rs17817449, KIF6 rs20455, 9p21 rs10757274 and 2q36.3 rs2943634) on CVD manifestation, and determine whether this effect differs between younger (< 50 years) and older CVD patients. METHODS: 1191 controls and 1889 MI patients were analyzed. All participants were Caucasian Czech males aged <65 years (532 were <50 years) who were examined at cardiology clinics in Prague, Czech Republic. Variants of FTO, 9p21, 2q36.3, and KIF-6 were genotyped using PCR-RFLP or TaqMan assay. RESULTS: Variants of FTO (OR 1.48; 95% CI, 1.19-1.84 in a TT vs. GG comparison, p=0.0005); 9p21 (OR 1.74; 95% CI, 1.41-2.14 in an AA vs. GG comparison, p=0.0001); and 2q36.3 (OR 1.34; 95%CI, 1.09-1.65 in an AA vs. +C comparison, p=0.006) were significantly associated with MI in the male Czech population. In contrast, genotype frequencies of KIF-6 (rs20455) were the same in patients and controls (P=1.00). Nearly identical results were observed when a subset of young MI patients (N=532, aged <50 years) was analyzed. CONCLUSION: We confirmed the importance of determining FTO, 9p21, and 2q36.3 variants as part of the genetic determination of MI risk in the Czech male population.

Strong gender-specific additive effects of the NYD-SP18 and FTO variants on BMI values.

The role of the FTO gene in obesity development is well established in populations around the world. The NYD-SP18 variant has been suggested to have a similar effect on BMI, but the role of this gene in determining BMI has not yet been verified. The objective of our study was to confirm the association between NYD-SP18 rs6971019 SNP and BMI in the Slavic population and to analyze i) the gender-specific effects of NYD-SP18 on BMI and ii) the simultaneous effect of FTO rs17817449 and NYD-SP18 on BMI. We analyzed a sample of a large adult population based on the post-MONICA study (1,191 males and 1,368 females). Individuals were analyzed three times over 9 years. NYD-SP18 rs6971019 SNP is related to BMI in males (2000/1 GG 28.3+/-3.7 kg/m(2) vs. +A 27.5+/-3.7 kg/m(2) P<0.0005; in other examinations P<0.05 and <0.005), but not in females (all P values over 0.48 in all three examinations). Further analysis revealed the significant additive effect (but not the interaction) of FTO and NYD-SP18 SNPs on BMI in males (all P<0.01). These results suggest that association between NYD-SP18 rs6971019 SNP and BMI may be restricted to males. Furthermore, variants within NYD-SP18 and FTO genes revealed a significant additive effect on BMI values in males.

Comparison of the relative telomere length measured in leukocytes and eleven different human tissues.

The relative length of telomeres measured in peripheral blood leukocytes is a commonly used system marker for biological aging and can also be used as a biomarker of cardiovascular aging. However, to what extent the telomere length in peripheral leukocytes reflects telomere length in different organ tissues is still unclear. Therefore, we have measured relative telomere length (rTL) in twelve different human tissues (peripheral blood leukocytes, liver, kidney, heart, spleen, brain, skin, triceps, tongue mucosa, intercostal skeletal muscle, subcutaneous fat, and abdominal fat) from twelve cadavers (age range of 29 week of gestation to 88 years old). The highest rTL variability was observed in peripheral leukocytes, and the lowest variability was found in brain. We found a significant linear correlation between leukocyte rTL and both intercostal muscle (R=0.68, P<0.02) and liver rTL (R=0.60, P<0.05) only. High rTL variability was observed between different organs from one individual. Furthermore, we have shown that even slight DNA degradation (modeled by sonication of genomic DNA) leads to false rTL shortening. We conclude that the rTL in peripheral leukocytes is not strongly correlated with the rTL in different organs.

FTO and MC4R gene variants determine BMI changes in children after intensive lifestyle intervention.

OBJECTIVES: This study aimed to determine whether there is a relationship between common FTO (rs17817449) and MC4R (rs17782313) gene variants and body mass reduction or weight loss after a one-month lifestyle intervention in overweight/obese children. DESIGN AND METHODS: We genotyped 357 unrelated non-diabetic Czech children (age 13.7 ± 4.9 years, average BMI at baseline 30.8 ± 4.6 kg/m(2)). Biochemical and anthropometrical measurements were performed before and after 4 weeks of lifestyle interventions (comprising a reduction in energy intake to the age-matched optimum and a supervised exercise program consisting of 5 exercise units per day, 50 min each). RESULTS: The mean weight loss achieved was 6.2 ± 2.1 kg (P<0.001). Significant associations were found between a BMI decrease and the FTO and MC4R variants. Carriers of the FTO GG genotype and/or MC4R CC genotype lost significantly more body weight compared to noncarriers (P<0.0009 for BMI and P<0.002 for body weight). These differences remained significant following adjustment for sex, age and baseline values (P=0.004 for BMI and P=0.01 for body weight). CONCLUSIONS: FTO and MC4R gene variants modify the impact of an intensive lifestyle intervention on BMI decrease in overweight/obese children. Carriers of the FTO GG genotype and MC4R CC genotype benefit significantly more from the lifestyle intervention.

Impact of variants within seven candidate genes on statin treatment efficacy.

Statins are the most commonly used drugs in patients with dyslipidemia. Among the patients, a significant inter-individual variability with supposed strong genetic background in statin treatment efficacy has been observed. Genome wide screenings detected variants within the CELSR2/PSRC1/SORT1, CILP2/PBX4, APOB, APOE/C1/C4, HMGCoA reductase, LDL receptor and PCSK9 genes that are among the candidates potentially modifying response to statins. Ten variants (SNPs) within these genes (rs599838, rs646776, rs16996148, rs693, rs515135, rs4420638, rs12654264, rs6511720, rs6235, rs11206510) were analyzed in 895 (46 % men, average age 60.3+/-13.1 years) patients with dyslipidemia treated with equipotent doses of statins (~90 % on simvastatin or atorvastatin, doses 10 or 20 mg) and selected 672 normolipidemic controls (40 % men, average age 46.5 years). Lipid parameters were available prior to the treatment and after 12 weeks of therapy. Statin treatment resulted in a significant decrease of both total cholesterol (7.00+/-1.53-->5.15+/-1.17 mmol/l, P<0.0001) and triglycerides (2.03+/-1.01-->1.65+/-1.23 mmol/l, P<0.0005). Rs599838 variant was not detected in first analyzed 284 patients. After adjustment for multiple testing, there was no significant association between individual SNPs and statin treatment efficacy. Only the rs4420638 (APOE/C1/C4 gene cluster) G allele carriers seem to show more profitable change of HDL cholesterol (P=0.007 without and P=0.06 after adjustment). Results demonstrated that, although associated with plasma TC and LDL cholesterol per se, variants within the CELSR2/PSRC1/SORT1, CILP2/PBX4, APOB, APOE/C1/C4, HMGCoA reductase, LDL receptor and PCSK9 genes do not modify therapeutic response to statins.

Association between FTO 1st intron tagging variant and telomere length in middle aged females. 3PMFs study.

The FTO gene plays an important role in the determination of body weight and BMI and it has been suspected of being associated with all-cause mortality, cardiovascular disease, cancer and end stage renal disease, but the causal mechanism of these effects is still unknown. One of the possibilities is the potential association with telomere length. Telomeres are repetitive DNA-sequences located at the ends of eukaryotic chromosomes' length of which is reduced in all somatic cells during ageing. Out of the 908 females (3PMFs study), in 783 females both FTO 1st intron tagging polymorphism (G>T, rs17817449) and the relative telomere length were successfully analysed. The relative telomere length was calculated as the ratio of telomere repeats to single-copy gene copies. The frequencies of the FTO genotypes were similar to other populations (GG=18.3%, GT=49.1% and TT=32.6%). We have detected, that the relative telomere length was significantly shorter (P<0.02, P<0.01 after adjustment for age, BMI, waist and subcutaneous fat), in carriers of at least one FTO risky (G) allele (0.85±0.39) in comparison to the carriers of the protective TT genotype (0.93±0.48). We have demonstrated that the FTO variant could be associated with the relative telomere length. Whether this represents a causality of association between the FTO variant and the non-communicable diseases needs to be further analysed.

[FTO gene and his role in genetic determination of obesity]. / Gen pro FTO a jeho role v genetické determinaci obezity.

Obesity is a risk factor for development of cardiovascular disease, type 2 diabetes and some cancers. Substantial proportions of obese people die from diseases caused by complications of overweight. The incidence of obesity in different populations exceeds 15%. The emergence of obesity is influenced by external factors (especially excessive energy intake and reduced physical activity). Body Mass Index (BMI) is also influenced by genetic factors, estimates of the degree of inheritance of obesity, according to the type of study range from 30 to 70%. Newly detected genetic risk factor for body weight is the FTO gene ("fat mass and obesity associated"). Variants in the first (and in some populations also in the third) intron of this gene are associated with BMI values and the presence of one risk allele is associated with an increase of body weight by about 1.5-2 kg. Studies on the possible causality (impact on energy intake, basal metabolism, physical activity) did not show consistent results. Variants in the first intron are also associated with higher risk of type 2 diabetes, polycystic ovary syndrome, and cardiovascular disease and seem to play a role in the determination of certain types of cancer and are associated with higher mortality. The exact mechanism of the effect of FTO on BMI determination is not yet known, however, the FTO exhibit a DNA demethylase activity and its role is designed as a transcription coactivator.

Body mass index change in females after short-time life style intervention is not dependent on the FTO polymorphisms.

Variants within the FTO gene are important determinants of body mass index (BMI), but their role in determination of BMI changes after combined dietary/physical activity intervention is unclear. We have analyzed 107 unrelated overweight non-diabetic Czech females (BMI over 27.5 kg/m(2), age 49.2+/-12.3 years). FTO variants rs17817449 (first intron) and rs17818902 (third intron) were genotyped. The life style modification program (10 weeks) consisted of an age-matched reduction of energy intake and exercise program (aerobic exercise 4 times a week, 60 min each). The mean BMI before intervention was 32.8+/-4.2 kg/m(2) and the mean achieved weight loss was 4.8+/-3.5 kg (5.3+/-3.5 %, max. -15.5 kg, min. +2.0 kg, p<0.01). No significant association between BMI decrease and FTO variants was found. Also waist-to-hip ratio, body composition (body fat, water, active tissue), lipid parameters (total, LDL and HDL cholesterol, triglycerides) glucose and hsCRP changes were independent on FTO variants. FTO variants rs17817449 and rs17818902 are not associated with BMI changes after combined short time dietary/physical activity intervention in overweight females.