The Association of Vitamin D Receptor Polymorphisms with COVID-19 Severity.

BACKGROUND: Association studies of vitamin D receptor (VDR) polymorphisms with COVID-19 severity have produced inconsistent results in different populations. Herein we examined VDR gene polymorphisms in a Caucasian Greek cohort of COVID-19 patients. METHODS: This was a case-control study in a tertiary university hospital in Greece including 137 COVID-19 patients with varying disease severities and 72 healthy individuals. In total 209 individuals were genotyped for the FokI (rs10735810), ApaI (rs7975232), TaqI (rs731236) and BsmI (rs1544410) single-nucleotide polymorphisms (SNP) of the VDR gene by polymerase chain reaction and restriction fragment length polymorphism analysis (PCR-RFLPs). Statistical analyses were performed to determine the association between genotype and disease severity, adjusting for various confounding factors. RESULTS: Genotype distribution of the studied VDR SNPs in the control group was in Hardy-Weinberg equilibrium. The TaqI variant was differentially distributed between controls and COVID-19 patients according to the additive model (p = 0.009), and the CC genotype was significantly associated with an increased risk for severe COVID-19 according to the recessive model [OR: 2.52, 95%CI:1.2-5.29, p = 0.01]. Multivariate analysis demonstrated a robust association of COVID-19 severity and TaqI polymorphism in the recessive model even after adjusting for multiple confounders, including age, sex and CRP levels [Adj.OR:3.23, 95%CI:1.17-8.86, p = 0.023]. The distribution of FokI, ApaI and BsmI genotypes was similar between COVID-19 patients and controls. CONCLUSIONS: The CC genotype of TaqI polymorphism is significantly associated with an increased risk for severe COVID-19 independently of age, sex or degree of inflammation.

Haloperidol's Cytogenetic Effect on T Lymphocytes of Systemic Lupus Erythematosus and Rheumatoid Arthritis Patients: An In Vitro Study.

OBJECTIVES: Investigating haloperidol's cytogenetic behavior in cultured human T lymphocytes of patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: Four haloperidol solutions were added in cultures of peripheral blood lymphocytes of healthy individuals, SLE, and RA patients. After 72 hours of incubation, the cultured lymphocytes were plated on glass slides, and stained with the fluorescence plus Giemsa method, and sister chromatid exchanges (SCEs), proliferation rate index (PRI), and mitotic index (MI) were measured with the optical microscope. RESULTS: Result analysis revealed: (a) a statistically significant (p=0.001) dose-dependent increase of SCEs in SLE patients compared to healthy individuals; (b) a statistically significant (p=0.001) dose-dependent decrease of SCEs in RA patients for haloperidol concentrations 5, 10µg/mL; (c) a statistically significant (p=0.001) dose-dependent increase of SCEs in RA patients for haloperidol concentrations 20, 100µg/mL; and (d) a statistically significant (p=0.001) dose-dependent reduction of PRI and MI in both patient groups compared to healthy individuals. Furthermore, a correlation was observed between (a) SCE and PRI index variations, (b) MI and SCE index variations, and (c) PRI and MI index variations. CONCLUSIONS: Haloperidol affects T lymphocytes from SLE and RA patients by modifying DNA replication procedures, DNA damage response, and ferroptosis. Considering the wide use of haloperidol in neuropsychiatric symptoms of SLE and RA patients, further studies with more immune cell subsets are needed to evaluate its effects on human genetic material.

Olanzapine's Cytogenetic Effect on T Lymphocytes in Systemic Lupus Erythematosus and Rheumatoid Arthritis Patients: In Vitro Study.

OBJECTIVES: This study will investigate olanzapine's cytogenetic behavior in cultured human T lymphocytes in patients with systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). METHODS: Three olanzapine solutions were added in cultures of peripheral blood lymphocytes of healthy individuals, SLE, and RA patients. After 72 hours of incubation, the cultured lymphocytes were plated on glass slides and stained with the fluorescence plus Giemsa method. Sister chromatid exchanges (SCEs), proliferation rate index (PRI), and mitotic index (MI) were measured with the optical microscope. RESULTS: There was a statistically significant (p=0.001) dose-dependent increase of SCEs in SLE and RA patients compared to healthy individuals and a statistically significant (p=0.001) reduction of PRI and MI in the highest concentration in the SLE group. Moreover, Spearman's rank correlation coefficient was applied to calculate the correlation between SCEs, PRI, and MI. Negative significant correlations were noticed for both patient groups concerning SCEs-PRI alterations and SCEs-MI alterations. Conversely, positive correlations were noticed for both patient groups for PRI-MI alterations.  Conclusions: Olanzapine affects T lymphocytes from SLE and RA patients by modifying DNA replication procedures and DNA damage response. Considering the use of olanzapine in neuropsychiatric symptoms of SLE, further in vivo studies are necessary to evaluate its effect on human DNA.

Oxytocin preprotein and oxytocin receptor mRNA expression is altered in semen samples with abnormal semen parameters.

RESEARCH QUESTION: Are oxytocin preprotein and the oxytocin receptor expressed in human spermatozoa and is their mRNA expression different between normal semen samples and samples with at least one abnormal parameter? DESIGN: An in-vitro prospective study of 175 semen samples from Greek men, according to World Health Organization criteria, 2010. mRNA expression levels were compared between different categories of semen samples, classified according to their concentration, total number, motility and morphology. Immunohistochemistry was used to detect oxytocin preprotein and its receptor on spermatozoa smears. RESULTS: Compared with normal samples (normal motility and normal concentration), samples with at least one abnormal sperm parameter had statistically significantly lower oxytocin preprotein mRNA expression (P = 0.019) and higher oxytocin receptor mRNA expression levels (P < 0.001). Oligozoospermic samples had statistically significantly higher oxytocin preprotein mRNA expression levels (P = 0.002) and lower oxytocin receptor mRNA expression levels (P = 0.047). Asthenozoospermic samples had statistically significantly lower oxytocin preprotein mRNA expression levels (P < 0.001). Teratozoospermic samples had statistically significantly lower oxytocin preprotein mRNA expression levels (P = 0.049) and higher oxytocin receptor mRNA expression levels (P < 0.001). Oxytocin preprotein mRNA expression was positively associated with total progressive motility (P < 0.001) and negatively associated with the percentage of immotile spermatozoa (P = 0.001). Oxytocin receptor mRNA expression was negatively associated with the percentage of normal forms (P < 0.001). CONCLUSION: Oxytocin preprotein and oxytocin receptor mRNA expression in spermatozoa could be used as a novel and unbiased diagnostic tool for male infertility.

Effect of Bladder Injection of OnabotulinumtoxinA on the Central Expression of Genes Associated with the Control of the Lower Urinary Tract: A Study in Normal Rats.

To investigate a possible central mechanism of action of Botulinum toxin A (BoNT/A) following injection in the bladder, complementary to the acknowledged peripheral bladder effect, we studied changes in the expression of neuropeptides and receptors involved in lower urinary tract function in the spinal cord (SC) and dorsal root ganglia (DRG) of normal rats following BoNT/A bladder injection. Thirty-six Sprague-Dawley rats, divided into three groups of n = 12, received bladder injections of 2U or 5U OnabotulinumtoxinA (BOTOX®), or saline. Six animals from each group were sacrificed on days 7 and 14. Expression of Tachykinin 1 (Tac1), capsaicin receptor (TRPV1), neuropeptide Y (NPY), proenkephalin (PENK) and muscarinic receptors M1, M2, M3, was evaluated in the bladder, L6-S1 DRG, and SC segments using real-time PCR and Western blotting. Real-time PCR revealed increased expression of NPY in all tissues except for SC, and increased TRPV1 and PENK expression in DRG and SC, whereas expression of Tac1, M1 and M2 was decreased. Less significant changes were noted in protein levels. These findings suggest that bladder injections of OnabotulinumtoxinA may be followed by changes in the expression of sensory, sympathetic and cholinergic bladder function regulators at the DRG/SC level.

Association of rs738409 Polymorphism in Adiponutrin Gene with Liver Steatosis and Atherosclerosis Risk Factors in Greek Children and Adolescents.

Non-alcoholic fatty liver disease (NAFLD) shares several risk factors with atherosclerosis, as it is associated with components of the metabolic syndrome. However, genetic variations have also been linked to the risk of NAFLD, such as adiponutrin/patatin-like phospholipase domain-containing the protein 3 (PNPLA3) rs738409 polymorphism. The aim of the study was to determine the associations of thePNPLA3 rs738409 polymorphism with NAFLD and atherosclerosis risk factors in children and adolescents from northern Greece. A total of 91 children/adolescents who followed a Mediterranean eating pattern with no particular restrictions were studied. They were divided into three subgroups, according to their body mass index (BMI) and the presence or absence of liver disease. Diagnosis of NAFLD was based on a liver ultrasound, while the distribution of the PNPLA3 rs738409 polymorphism was investigated in all the participants. From the components of metabolic syndrome, only BMI, waist circumference, blood pressure, and the homeostasis model of insulin resistance (HOMA-IR) differed significantly between groups. The rs738409 polymorphism was significantly associated with BMI and NAFLD, while lipid values had no significant association with either NAFLD or gene polymorphism. This study shows that in Greekchildren, there is a significant association between the rs738409polymorphism in the PNPLA3 gene and hepatic steatosis, regardless of bodyweight.

Improvement in sperm quality by oral antioxidant supplementation in infertile men with varicocele who have not undergone surgical repair: Systematic review and meta-analysis.

The aim of this systematic review and meta-analysis was to assess whether oral antioxidant supplementation improves sperm quality in men with infertility and varicocele (VCL) who have not undergone surgical repair. In men with infertility and VCL who had not undergone surgical repair oral antioxidant supplementation significantly increased sperm concentration (WMD +5.86 × 106 /ml 95% CI: +1.47 to +10.24, p < 0.01; random effects model, six studies, 213 patients), total motility (WMD + 3.76%, 95% CI: +0.18 to +7.34, p = 0.04; random effects model, three studies, 93 patients), progressive motility (WMD + 6.38%, 95% CI: +3.04 to +9.71, p < 0.01; random effects model, three studies, 84 patients) and seminal volume (WMD +0.55 ml, 95%CI: +0.06 to +1.04, p = 0.03; random effects model, four studies, 120 patients). On the other hand, no significance difference was observed in sperm morphology (WMD +3.89%, 95% CI: -0.14 to +7.92, p = 0.06; random effects model, five studies, 187 patients). In conclusion, limited evidence suggests that the use of oral antioxidants in men with infertility and VCL, who have not undergone surgical repair improves their seminal volume, sperm concentration, total and progressive motility.

Association between rs738409 and rs2896019 single-nucleotide polymorphisms of phospholipase domain-containing protein 3 and susceptibility to nonalcoholic fatty liver disease in Greek children and adolescents.

Background: Several studies have detected a strong association linking rs738409 and rs2896019 polymorphisms in the patatin-like phospholipase domain-containing protein 3 (PNPLA3) gene with hepatic steatosis and steatohepatitis. In the present study we aimed to determine the association of those PNPLA3 variants with nonalcoholic fatty liver disease (NAFLD) susceptibility in obese and nonobese Greek children and adolescents. Methods: The study recruited 91 children and adolescents of Greek descent with NAFLD or biopsy-proven nonalcoholic steatohepatitis, and 91 healthy subjects of normal weight (control group) with sex distribution similar to the patient group. DNA samples were amplified using polymerase chain reaction with specifically designed primers. Data were analyzed using the statistical software SPSS version 24.0. Results: A significant correlation was shown between the rs738409 polymorphism (CG and GG genotypes) and the rs2896019 polymorphism (TG genotype) with the development of hepatic steatosis (P<0.001). The incidences of rs738409 GG, rs738409 CG and rs2896019 TG genotypes were found to be increased in patients with hepatic steatosis (obese and nonobese), but not in obese patients without liver disease. The combined expression of the 2 polymorphisms was associated with a lower age of diagnosis of hepatic steatosis in nonobese patients. Conclusions: We confirmed a strong association between the 2 polymorphisms and hepatic steatosis. The association of the rs2896019 single-nucleotide polymorphism with hepatic steatosis in obese and nonobese pediatric patients, and the combined study of both polymorphisms in a pediatric population of Greek origin are described for the first time.

Influence of conception and delivery mode on stress response marker Oct4B1 and imprinted gene expression related to embryo development: A cohort study.

BACKGROUND: Recent scientific data support that the mode of conception and delivery may influence epigenetic regulation and therefore embryo development. Octamer-binding transcription factor 4-B1 (OCT4B1), a novel variant of OCT4 with yet unknown biological function, is suggested to have a potential role in mediating cellular stress response. Furthermore, Insulinlike Growth Factor 2 (IGF2), Mesoderm-specific Transcript (MEST) and paternally expressed gene 10 (PEG10) are genes known as imprinted and are regulated via means of epigenetic regulation. The influence of delivery mode and conception on epigenetic regulation is an active research field. OBJECTIVE: Our aim was to correlate the expression level of Oct4B1 and the expression and methylation level of IGF2, MEST, and PEG10 imprinted genes with the mode of delivery and conception in the umbilical cord blood of newborns. MATERIALS AND METHODS: Samples of umbilical cord blood from infants born after vaginal delivery, caesarean section (CS) with the infant in cephalic position and CS due to breech position were examined. Furthermore, the investigation included infants conceived through means of assisted reproductive technology. RESULTS: No statistically significant differences were found in mRNA expression levels between different modes of conception and delivery (p = 0.96). Oct4B1, IGF2, MEST, and PEG10 expression levels do not seem to be significantly affected by different modes of conception and delivery. CONCLUSION: These results indicate that the expression and methylation patterns of Oct4B1, IGF2, MEST and PEG10 in umbilical cord blood are not affected by the conception and delivery mode.

Expression of genes that regulate follicle development and maturation during ovarian stimulation in poor responders.

RESEARCH QUESTION: Sex hormone-binding globulin (SHBG), androgen receptor (AR), LH beta polypeptide (LHB), progesterone receptor membrane component 1 (PGRMC1) and progesterone receptor membrane component 2 (PGRMC2) regulate follicle development and maturation. Their mRNA expression was assessed in peripheral blood mononuclear cells (PBMC) of normal and poor responders, during ovarian stimulation. DESIGN: Fifty-two normal responders and 15 poor responders according to the Bologna criteria were enrolled for IVF and intracytoplasmic sperm injection and stimulated with 200 IU of follitrophin alpha and gonadotrophin-releasing hormone antagonist. HCG was administered for final oocyte maturation. On days 1, 6 and 10 of stimulation, blood samples were obtained, serum hormone levels were measured, RNA was extracted from PBMC and real-time polymerase chain reaction was carried out to identify the mRNA levels. Relative mRNA expression of each gene was calculated by the comparative 2-DDCt method. RESULTS: Differences between mRNA levels of each gene on the same time point between the two groups were not significant. PGRMC1 and PGRMC2 mRNA levels were downregulated, adjusted for ovarian response and age. Positive correlations between PGRMC1 and AR (standardized beta = 0.890, P < 0.001) from day 1 to 6 and PGRMC1 and LHB (standardized beta = 0.806, P < 0.001) from day 1 to 10 were found in poor responders. PGRMC1 and PGRMC2 were positively correlated on days 6 and 10 in normal responders. CONCLUSIONS: PGRMC1 and PGRMC2 mRNA are significantly decreased during ovarian stimulation, with some potential differences between normal and poor responders.

In-utero stress and mode of conception: impact on regulation of imprinted genes, fetal development and future health.

BACKGROUND: Genomic imprinting is an epigenetic gene regulatory mechanism; disruption of this process during early embryonic development can have major consequences on both fetal and placental development. The periconceptional period and intrauterine life are crucial for determining long-term susceptibility to diseases. Treatments and procedures in assisted reproductive technologies (ART) and adverse in-utero environments may modify the methylation levels of genomic imprinting regions, including insulin-like growth factor 2 (IGF2)/H19, mesoderm-specific transcript (MEST), and paternally expressed gene 10 (PEG10), affecting the development of the fetus. ART, maternal psychological stress, and gestational exposures to chemicals are common stressors suspected to alter global epigenetic patterns including imprinted genes. OBJECTIVE AND RATIONALE: Our objective is to highlight the effect of conception mode and maternal psychological stress on fetal development. Specifically, we monitor fetal programming, regulation of imprinted genes, fetal growth, and long-term disease risk, using the imprinted genes IGF2/H19, MEST, and PEG10 as examples. The possible role of environmental chemicals in genomic imprinting is also discussed. SEARCH METHODS: A PubMed search of articles published mostly from 2005 to 2019 was conducted using search terms IGF2/H19, MEST, PEG10, imprinted genes, DNA methylation, gene expression, and imprinting disorders (IDs). Studies focusing on maternal prenatal stress, psychological well-being, environmental chemicals, ART, and placental/fetal development were evaluated and included in this review. OUTCOMES: IGF2/H19, MEST, and PEG10 imprinted genes have a broad developmental effect on fetal growth and birth weight variation. Their disruption is linked to pregnancy complications, metabolic disorders, cognitive impairment, and cancer. Adverse early environment has a major impact on the developing fetus, affecting mostly growth, the structure, and subsequent function of the hypothalamic-pituitary-adrenal axis and neurodevelopment. Extensive evidence suggests that the gestational environment has an impact on epigenetic patterns including imprinting, which can lead to adverse long-term outcomes in the offspring. Environmental stressors such as maternal prenatal psychological stress have been found to associate with altered DNA methylation patterns in placenta and to affect fetal development. Studies conducted during the past decades have suggested that ART pregnancies are at a higher risk for a number of complications such as birth defects and IDs. ART procedures involve multiple steps that are conducted during critical windows for imprinting establishment and maintenance, necessitating long-term evaluation of children conceived through ART. Exposure to environmental chemicals can affect placental imprinting and fetal growth both in humans and in experimental animals. Therefore, their role in imprinting should be better elucidated, considering the ubiquitous exposure to these chemicals. WIDER IMPLICATIONS: Dysregulation of imprinted genes is a plausible mechanism linking stressors such as maternal psychological stress, conception using ART, and chemical exposures with fetal growth. It is expected that a greater understanding of the role of imprinted genes and their regulation in fetal development will provide insights for clinical prevention and management of growth and IDs. In a broader context, evidence connecting impaired imprinted gene function to common diseases such as cancer is increasing. This implies early regulation of imprinting may enable control of long-term human health, reducing the burden of disease in the population in years to come.

The Role of TLR4 Asp299Gly and TLR4 Thr399Ile Polymorphisms in the Pathogenesis of Urinary Tract Infections: First Evaluation in Infants and Children of Greek Origin.

Urinary tract infections are one of the most common and serious bacterial infections in a pediatric population. So far, they have mainly been related to age, gender, ethnicity, socioeconomic level, and the presence of underlying anatomical or functional, congenital, or acquired abnormalities. Recently, both innate and adaptive immunities and their interaction in the pathogenesis and the development of UTIs have been studied. The aim of this study was to assess the role and the effect of the two most frequent polymorphisms of TLR4 Asp299Gly and Thr399Ile on the development of UTIs in infants and children of Greek origin. We studied 51 infants and children with at least one episode of acute urinary tract infection and 109 healthy infants and children. We found that 27.5% of patients and 8.26% of healthy children carried the heterozygote genotype for TLR4 Asp299Gly. TLR4 Thr399Ile polymorphism was found to be higher in healthy children and lower in the patient group. No homozygosity for both studied polymorphisms was detected in our patients. In the group of healthy children, a homozygote genotype for TLR4 Asp299Gly (G/G) as well as for TLR4 Thr399Ile (T/T) was showed (1.84% and 0.92 respectively). These results indicate the role of TLR4 polymorphism as a genetic risk for the development of UTIs in infants and children of Greek origin.

Association of NFKB1 -94ATTG ins/del polymorphism (rs28362491) with pemphigus vulgaris.

Pemphigus vulgaris is a rare chronic blistering skin disease resulting from IgG autoantibodies directed against transmembrane desmosomal glycoprotein desmoglein 3 and is the most common form of pemphigus. Since interleukin-1 receptor-associated kinase (IRAK-1)/nuclear factor-kappa B (NF-kappa B) pathway plays an essential role in the pathogenesis of autoimmune diseases, the aim of the present study was to explore the role of polymorphisms in three genes, named IRAK1 (rs3027898), NFKBIA (rs696) and NFKB1 (-94ATTG insertion/deletion variant, - rs28362491), in PV susceptibility. Forty-four unrelated patients with PV (23 males) were enrolled in the study. Additionally, 77 ethnic matching healthy volunteers (45 males) with no personal or family history of chronic autoimmune or infectious diseases were studied. Strong statistical significant difference was observed between PV patients and controls for polymorphism -94 insertion/deletion ATTG in the promoter region of NFKB1 gene (P = 0.00005). Additional dedicated studies in larger groups of patients of various ethnicities are needed to replicate and confirm the preliminary findings.

The protective variant rs7173049 at LOXL1 locus impacts on retinoic acid signaling pathway in pseudoexfoliation syndrome.

LOXL1 (lysyl oxidase-like 1) has been identified as the major effect locus in pseudoexfoliation (PEX) syndrome, a fibrotic disorder of the extracellular matrix and frequent cause of chronic open-angle glaucoma. However, all known PEX-associated common variants show allele effect reversal in populations of different ancestry, casting doubt on their biological significance. Based on extensive LOXL1 deep sequencing, we report here the identification of a common non-coding sequence variant, rs7173049A>G, located downstream of LOXL1, consistently associated with a decrease in PEX risk (odds ratio, OR = 0.63; P = 6.33 × 10-31) in nine different ethnic populations. We provide experimental evidence for a functional enhancer-like regulatory activity of the genomic region surrounding rs7173049 influencing expression levels of ISLR2 (immunoglobulin superfamily containing leucine-rich repeat protein 2) and STRA6 [stimulated by retinoic acid (RA) receptor 6], apparently mediated by allele-specific binding of the transcription factor thyroid hormone receptor beta. We further show that the protective rs7173049-G allele correlates with increased tissue expression levels of ISLR2 and STRA6 and that both genes are significantly downregulated in tissues of PEX patients together with other key components of the STRA6 receptor-driven RA signaling pathway. siRNA-mediated downregulation of RA signaling induces upregulation of LOXL1 and PEX-associated matrix genes in PEX-relevant cell types. These data indicate that dysregulation of STRA6 and impaired retinoid metabolism are involved in the pathophysiology of PEX syndrome and that the variant rs7173049-G, which represents the first common variant at the broad LOXL1 locus without allele effect reversal, mediates a protective effect through upregulation of STRA6 in ocular tissues.

Detection of IgG Autoantibodies against Desmocollin-3 in Greek Patients with Pemphigus.

Pemphigus is an autoimmune bullous disorder caused by autoantibodies against desmosomal cadherins. The most common clinical forms are pemphigus vulgaris (PV) and pemphigus foliaceus (PF). Among the numerous proteins that are considered responsible for the cohesion of keratinocytes in epidermis, desmocollin-3 (Dsc-3) has been initially reported to participate in epidermal blistering in mice. There have been reports in which autoantibodies against Dsc-3 have been detected. In PV, a limited number of studies found no presence of IgG or IgA autoantibodies against Dsc-3. In this study we examined sera from Greek patients with PV and PF for the presence of IgG autoantibodies against Dsc-3. Immunoblotting for the detection of autoantibodies against Dsc-3 was performed in sera from all cases. Dsc-3 autoantibodies were not detected in either group (PV and PF). Our results confirm the hypothesis that the pathogenic role of Dsc-3 in epidermal blistering in PV and PF remains controversial.

MicroRNA-related polymorphisms in pseudoexfoliation syndrome, pseudoexfoliative glaucoma, and primary open-angle glaucoma.

BACKGROUND: Pseudoexfoliation syndrome (PEX) and glaucoma (pseudoexfoliative glaucoma; PEXG, primary open-angle glaucoma; POAG) have mainly been studied for their associations with genes' polymorphisms. The purpose of this exploratory study was to investigate the role of polymorphisms in genes encoding for micro RNAs (miRNAs) and in genes related to miRNA biogenesis. MATERIAL AND METHODS: In the present genetic association study, ninety-two polymorphisms were investigated for their contribution to PEX (n = 203), PEXG (n = 38), and POAG (n = 40) pathogenesis compared to a control group (n = 188). The next generation sequencing (NGS) genotypic analysis revealed data for additional 28 variants. RESULTS: A protective association was found between PEX and polymorphism 11382316 (mir-3161) [odds ratio (OR) = 0.64, 95% confidence interval (CI): 0.47-0.86, p = 0.003], rs2155248 (mir-1304) [OR = 0.66, 95%CI: 0.47-0.94, p = 0.019], and rs28635903 (mir-1268a) [OR = 0.30, 95%CI: 0.10-0.94, p = 0.029]. Polymorphism rs113297757 (mir-3196) was associated with an increased risk of POAG [OR = 7.75, 95%CI: 2.13-28.76, p = 3 × 10-4]. Polymorphism rs1057035 (DICER) and rs55671916 (XPO5) in the 3'-UTR of genes related to miRNA biogenesis was associated with decreased risk of PEX [OR = 0.65, 95%CI: 0.46-0.92, p = 0.014] and increased risk of PEXG [OR = 2.84, 95%CI: 1.02-7.94, p = 0.038], respectively. The aforementioned associations according to the allelic model were further supported by the genotypic models of statistical analyses. CONCLUSIONS: This is the first study to report distinct associations of PEX, PEXG, and POAG in the same population with variants of genes involved in miRNA biogenesis and with miRNA genes' polymorphisms. Further studies in larger groups of patients of various origins are needed to confirm the reported preliminary results.

Ethnicity-Based Differences in the Association of LOXL1 Polymorphisms with Pseudoexfoliation/Pseudoexfoliative Glaucoma: A Meta-Analysis.

Pseudoexfoliation (PEX) is an age-related disorder of the extracellular matrix; it is strongly associated with glaucoma, the leading cause of irreversible blindness worldwide. We conducted an ethnic-based meta-analysis of the association of LOXL1 polymorphisms with PEX/pseudoexfoliative glaucoma (PEXG). Association studies were retrieved systematically from PubMed, EMBASE, and Web of Knowledge. Allelic and genotype frequencies of rs3825942, rs1048661, and rs2165241 were compared between PEX/PEXG and controls. Odds ratios (OR) and 95% confidence intervals (CI) were calculated using a random effects model. Overall, 39 independent cohorts were included. Rs3825942 (G) was an at risk allele for PEX/PEXG in Caucasians, Japanese, Koreans, Chinese, South Asians, and Middle Easterners, but protective in Black South Africans (OR = 0.10, 95%CI:0.06-0.16). Rs1048661 (G) was an at risk allele for PEX/PEXG in Caucasians, South Asians, Middle Easterners and Black South Africans, but was protective in Japanese (OR = 0.03, 95%CI:0.02-0.06) and Koreans (OR = 0.10, 95%CI:0.05-0.22). These associations we-re confirmed for the genotypic recessive models. Rs2165241 (C) was a protective allele for PEX/PEXG in Caucasians, but was an at risk allele in Japanese (OR = 7.49, 95%CI:3.22-17.41) and Koreans (OR = 6.63, 95%CI:2.60-16.90). This was confirmed for the genotypic dominant model. Other genetic and/or environmental factors may modify the effect of LOXL1 polymorphisms in certain ethnic groups.