Leukoaraiosis is associated with genes regulating blood–brain barrier homeostasis in ischaemic stroke patients

Background: The biologic agents causing leukoaraiosis are unknown. Our aim was to study the genetic basis of leukoaraiosis. Methods: We analyzed 212 single nucleotide polymorphisms (SNPs) in 142 patients with ischaemic stroke, generating a total of 30 104 genotypes. Seventy‐nine subjects (55.6%) presented leukoaraiosis measured by the Fazekas scale and 69 (48.6%) by ARWMC scale. We analyzed the presence of synergic associations between SNPs using the hfcc software. Finally, functional studies were performed in 56 subjects. The Ingenuity Pathways software (ipa ) was used to examine the role of the identified genes. Results: Six SNPs were associated with leukoaraiosis using both measuring scales. After logistic regression adjusted for leukoaraiosis risk factors, the rs2252070 of MMP13 (OR = 4.9, 95%CI: 1.34–17.9, P = 0.016), rs662 of PON1 (OR = 0.37, 95%CI: 0.15–0.87, P = 0.024) and rs1800779 of NOS3 (OR = 3.9, 95%CI: 1.38–11.38, P = 0.01) were independently associated with leukoaraiosis under a dominant/recessive model and the rs2290608 of IL5RA (OR = 0.46, 95%CI: 0.25–0.85, P = 0.013) and rs669 of A2M (OR = 2.5, 95%CI: 1.36–4.83, P = 0.004) under an additive model. Computational analysis showed a synergic association of rs10497212‐AA of ITGB6 and rs2290608‐GG of IL5RA with leukoaraiosis using both scales. (i) ARWMC (P = 1.3 × 10⁻⁴) and (ii) Fazekas (P = 4.5 × 10⁻⁵). Functional studies showed that the rs669 SNP was associated with plasma levels of A2M (P = 0.012) and A2M levels with leukoaraiosis in Fazekas scale (P = 0.02). ipa analysis revealed that the genes associated with leukoaraiosis were involved in blood–brain barrier (BBB) homeostasis. Conclusions: Amongst patients with ischaemic stroke, several genes associated with BBB homeostasis could be involved with a higher risk of leukoaraiosis.     

Association of the MAPT locus with Parkinson’s disease

Background and purpose: Whilst an association between the tau gene (MAPT)‐containing H1 haplotype and supranuclear gaze palsy (PSP) has long been recognized, the effect of H1 on risk for Parkinson’s disease (PD) has remained more contentious. Methods: Herein, we examined the association of H1 and PD in three Caucasian PD patient–control series from Ireland, Norway, and the US (combined: n = 2619), by genotyping two H1/H2 single nucleotide polymorphisms (SNPs) in MAPT (rs1052553) and in the Saitohin gene (rs62063857) and one H1‐specific SNP (rs242557). Results: We identified a significant association between H1/H2 and risk of PD (rs1052553 OR: 1.43, CI: 1.23–1.64; rs62063857 OR: 1.45, CI: 1.27–1.67), but no effect of the H1‐specific SNP rs242557 (OR: 0.92, CI: 0.82–1.03). Conclusions: Our findings show that the H1 haplotype is a significant risk factor for PD. However, one H1‐specific SNP (rs242557) previously implicated in PSP did not alter the risk of PD, indicating that distinct H1 sub‐haplotypes probably drive the associations with PD and PSP.     

Association between Parkinson's disease and the HLA‐DRB1 locus

Two genome‐wide association studies (GWASs) recently highlighted the HLA‐DRA and HLA‐DRB5 genes as associated with Parkinson disease (PD). However, because HLA‐DRA displays a low level of polymorphisms and HLA‐DRB5 is only present in approximately 20% of the population, these findings are difficult to interpret. Our aims were: (1) to replicate and investigate in greater detail the association between PD and the HLA‐DR region; (2) to identify PD‐associated HLA alleles; and (3) to perform a meta‐analysis of our top finding. As part of 2 French population‐based case–control studies of PD including highly ethnically homogeneous participants, we investigated the association between PD and 51 Single‐nucleotide polymorphisms (SNPs) in the HLA‐DR region. HLA‐DRB1 alleles were imputed using the HLA^*IMP software. HLA typing was performed in a subsample of the participants. We performed a meta‐analysis of our top finding based on 4 GWAS data sets. Among 499 cases and 1123 controls, after correction for multiple testing, we found an association with rs660895 (OR/minor allele, 0.70; 95% CI, 0.57–0.87) within the HLA‐DRB1 gene, which encodes the most polymorphic HLA‐DR chain (DRβ). A meta‐analysis (7996 cases, 36455 controls) confirmed this association (OR, 0.86; 95% CI, 0.82–0.91; P < .0001). SNP‐based imputation of HLA alleles showed an inverse association between PD and the HLA‐DRB1^*04 allele. We replicated an association between PD and the HLA‐DR region and provided further insight into the loci and alleles involved. The highly polymorphic HLA‐DRB1 locus contains rs660895, which represents a more legitimate candidate than previous ones. Our finding is in agreement with the hypothesis of an immune component in PD pathophysiology. © 2012 Movement Disorder Society     

Common variants in PARK loci and related genes and Parkinson's disease

Rare mutations in PARK loci genes cause Parkinson's disease (PD) in some families and isolated populations. We investigated the association of common variants in PARK loci and related genes with PD susceptibility and age at onset in an outbred population. A total of 1,103 PD cases from the upper Midwest, USA, were individually matched to unaffected siblings (n = 654) or unrelated controls (n = 449) from the same region. Using a sequencing approach in 25 cases and 25 controls, single nucleotide polymorphisms (SNPs) in species‐conserved regions of PARK loci and related genes were detected. We selected additional tag SNPs from the HapMap. We genotyped a total of 235 SNPs and two variable number tandem repeats in the ATP13A2, DJ1, LRRK1, LRRK2, MAPT, Omi/HtrA2, PARK2, PINK1, SNCA, SNCB, SNCG, SPR, and UCHL1 genes in all 2,206 subjects. Case‐control analyses were performed to study association with PD susceptibility, while cases‐only analyses were used to study association with age at onset. Only MAPT SNP rs2435200 was associated with PD susceptibility after correction for multiple testing (OR = 0.74, 95% CI = 0.64–0.86, uncorrected P < 0.0001, log additive model); however, 16 additional MAPT variants, seven SNCA variants, and one LRRK2, PARK2, and UCHL1 variants each had significant uncorrected P‐values. There were no significant associations for age at onset after correction for multiple testing. Our results confirm the association of MAPT and SNCA genes with PD susceptibility but show limited association of other PARK loci and related genes with PD. © 2010 Movement Disorder Society     

Interactions between four gene polymorphisms and their association with patients with Parkinson's disease in a Chinese Han population

The four previously reported Parkinson's disease (PD)-related single-nucleotide polymorphisms (SNPs) – rs1775143, rs823114, rs2071746 and rs62063857 – have rarely been studied in Chinese Han populations. To examine the association between these SNPs and PD, we conducted a case-control study of 158 patients with PD and 210 controls. All participants were Chinese Han from Northern China. With covariate adjustment for clinical characteristics, logistic regression analysis revealed no differences in genotype or allele frequencies for the four SNPs. Stratified by age of disease onset, sex, smoking status, duration of disease, baseline UPDRS, Hoehn–Yahr Stage, PD subtypes, scores of Hamilton anxiety scale, Hamilton depression scale and activity of daily living, all of the p values did not remain significant after Bonferroni correction. However, the haplotype rs1775143T-rs823114G-rs2071746T-rs62063857A was associated with increased risk of developing PD (p = 0.003, OR = 456.88, 95% CI: 27.40–7619.75) in our case-control sample set. The haplotype rs1775143T-rs823114G-rs2071746T was also associated with increased risk of developing PD (p = 0.003, OR = 338.43, 95% CI: 20.68–5538.27). Although the haplotype rs1775143T-rs823114G-rs62063857A was associated with increased risk of PD (p = 0.03), the 95% CI was 0.993–22.469. Our data demonstrate that although specific SNPs were not related with PD patients, certain haplotypes were associated with increased risk for PD in the Chinese Han population. These results provide further evidence that the etiology of PD is multifactorial, although the underling mechanism needs further study.     

Association of F11 polymorphism rs2289252 with deep vein thrombosis and related phenotypes in population of Latvia

Introduction

Deep vein thrombosis (DVT) has a strong inherited predisposition that is partly explained by the strong genetic risk factors such as mutations in factor V, prothrombin, antithrombin III, protein C and S genes. Only recently the first GWAS have been performed on DVT resulting in discovery of novel genetic variants, however, the information on the common polymorphisms predisposing to the risk of DVT is still scarce.

Materials and Methods

Here we selected six SNPs (rs5361 in SELE, rs2066865 in FGG, rs2227589 in SERPINC1, rs1613662 in GP6, rs13146272 in CYP4V2, rs2289252 in F11) reported to be associated with venous thrombosis conditions and studied the association of these common variants in selected case (n = 177) and control (n = 235) groups from population of Latvia. Genotyping was performed using TaqMan hybridization probe SNP genotyping assay.

Results

Patients with DVT had a significantly higher frequency of F11 rs2289252 polymorphism (p = 0.001; OR [95%CI] = 1.61 [1.20-2.14]). When stratified by recurrence of DVT the tendency was observed that the same SNP had higher OR value in group of DVT patients with repeated episodes of DVT compared to patients with single DVT episode (p = 0.009; OR [95%CI] = 2.27[1.22-4.21] and p = 0.009; OR [95%CI] = 1.52[1.11-2.08] respectively), but due to limited group of cases this finding should be replicated.

Conclusion

We conclude that F11 gene variant rs2289252 contribute to inherited forms of DVT incidence and correlation of other analysed SNPs should be explored in populations with greater sample size and associated with various thrombosis related traits.     

SNCA polymorphisms, smoking, and sporadic Parkinson's disease in Japanese

Several case-control studies and genome-wide association studies have examined the relationships between single nucleotide polymorphisms (SNPs) in the SNCA gene and Parkinson's disease (PD), and have provided inconsistent results. We investigated the relationships between SNPs rs356229, rs356219, rs356220, rs7684318, and rs2736990 and the risk of sporadic PD in Japan using data from a multicenter hospital-based case-control study. Included were 229 cases within 6 years of onset of PD as defined according to the UK PD Society Brain Bank clinical diagnostic criteria. Controls were 357 inpatients and outpatients without neurodegenerative disease. Adjustment was made for sex, age, region of residence, and smoking. Based on the recessive model, compared with subjects with the CC or CT genotype of SNP rs356220, those with the TT genotype had a significantly increased risk of sporadic PD: the adjusted OR was 1.42 (95% CI: 1.002-2.02). In the additive model, SNP rs2736990 was significantly related to the risk of sporadic PD: the adjusted OR was 1.30 (95% CI: 1.002-1.68). There were no significant relationships between SNP rs356229, rs356219, or rs7684318 and the risk of sporadic PD in any genetic model. The additive interactions between SNPs rs356219 and rs356220 and smoking with respect to sporadic PD were significant although the multiplicative interactions were not significant. This study suggests that SNCA SNPs rs356220 and rs2736990 are significantly associated with the risk of sporadic PD in Japanese. We also present new evidence for biological interactions between SNPs rs356219 and rs356220 and smoking that affect sporadic PD.     

The C allele of synonymous SNP (rs1142636, Asn170Asn) in SYN1 is a risk factor for the susceptibility of Korean female schizophrenia

Objective: The aim of this study was to investigate the association between the exonic single nucleotide polymorphisms (SNPs) of synapsin I (SYN1) (rs1142636, Asn170Asn, Xp11.23) and SYN2 (rs2289708, 3′‐untranslated region, 3p25) in schizopherenia. Methods: Two hundred eighty six schizophrenia patients and 304 control subjects were recruited. SNPs with a know heterozygosity and minor allele frequency (MAF) > 0.1 in Asian populations were selected and genotyped by direct sequencing. Results: The allelic frequencies of rs1142636 (SYN1) were associated with schizophrenia (P < 0.05), respectively. The allelic frequency of rs1142636 in all subjects was associated with schizophrenia [P = 0.000059, OR = 2.17 (95% CI = 1.47–3.18)]. The C allele frequency of rs1142636 was higher in schizophrenia (20.8%) than that in controls (10.8%). In the analysis of gender, the allelic frequency of rs1142636 was also strongly associated with female schizophrenia [P = 0.0001, OR = 2.65 (95% CI = 1.61–4.36)], but not with male schizophrenia. The C allele frequency of rs1142636 was higher in female schizophrenia (22.2%) than that in female controls (9.7%). The rs2289708 SNP (SYN2) did not show any association between schizophrenia and controls. Conclusions: These results suggest that the C allele of a synonymous SNP (rs1142636, Asn170Asn, Xp11.23) in SYN1 may be a risk factor for the susceptibility of Koreran female schizophrenia. Synapse 66:979–983, 2012. © 2012 Wiley Periodicals, Inc.     

Impact of CRP gene and additional gene–smoking interaction on ischemic stroke in a Chinese Han population

Aims: To investigate the association of C-reactive protein (CRP) gene single nucleotide polymorphisms (SNPs), additional gene–gene, and gene–smoking interaction with ischemic stroke (IS) risk.

Methods: Logistic regression is performed to investigate association between SNPs within CRP gene and IS risk. Generalized multifactor dimensionality reduction (GMDR) was used to analyze the gene–gene and gene–smoking interaction, cross-validation consistency, the testing balanced accuracy and the sign test were calculated.

Results: Logistic analysis showed that three SNPs were all associated with decreased IS risk in additive and dominant models. The IS risks were lower in carriers of homozygous mutant of rs2794521 polymorphism and heterozygous of rs3093059 and rs1205 than those with wild-type homozygotes genotype, OR (95%CI) were 0.62 (0.40–0.90), 0.68 (0.50–0.96) and 0.65 (0.46–0.97), respectively. GMDR analysis suggested a significant two-locus model (P = 0.0010) involving rs2794521 and rs3093059. We also found a significant two-locus model (P = 0.0010) involving rs2794521 and smoking. Participants with rs2794521-AG or GG and rs3093059-AG or GG genotype have the lowest IS risk, compared to participants with rs2794521-AA and rs3093059-AA genotype, OR (95%CI) was 0.4 2 (0.233–0.61). In addition, non-smokers with rs2794521-AG or GG genotype have the lowest IS risk, compared to smokers with rs2794521-AA genotype, OR (95%CI) was 0.47 (0.23–0.76).

Conclusions: We found that rs2794521, rs3093059, and rs1205 were associated with decreased IS risk; we also found that gene–gene interaction between rs2794521 and rs3093059, and gene–environment interaction between rs2794521 and smoking were associated with decreased IS risk.     

Impact of the PDE4D gene polymorphism and additional SNP–SNP and gene–smoking interaction on ischemic stroke risk in Chinese Han population

Aims: To investigate the association between phosphodiesterase 4D gene (PDE4D) gene single nucleotide polymorphisms (SNPs) and ischemic stroke (IS) risk, and impact of additional SNP- SNP and gene- smoking interaction on IS risk in Chinese population.

Methods: A total of 1228 subjects (666 males, 562 females) were selected, including 610 IS patients and 618 control subjects. Logistic regression model was used to examine the association between SNPs in PDE4D gene and IS risk. Generalized multifactor dimensionality reduction (GMDR) was employed to analyze the SNP- SNP and gene- smoking interaction.

Results: IS risks were significantly higher in carriers of A allele of rs12188950 polymorphism than those with GG genotype (GA + AA vs. GG), adjusted OR (95%CI) = 1.61 (1.26–2.19), and also significantly higher in carriers of T allele of rs966221 polymorphism than those with CC (CT + TT vs. CC), adjusted OR (95%CI) = 1.82 (1.39–2.23). We found that there was a significant SNP- SNP interaction between rs966221 and rs12188950. Subjects with CT or TT of rs966221 and GA or AA of rs12188950 genotype have the highest IS risk, compared to subjects with CC of rs966221 and GG of rs12188950 genotype, OR (95%CI) was 3.52 (2.68–4.69). We also found a significant gene–environment interaction between rs966221 and smoking. Smokers with CT or TT of rs966221 genotype have the highest IS risk, compared to never smokers with CC of rs966221 genotype, OR (95%CI) was 3.97 (2.25–5.71).

Conclusions: Our results support an important association of rs966221 and rs12188950 minor allele and its interaction with increased risk of IS risk, and additional interaction between rs966221 and smoking.     

Genetic Polymorphisms in Pre-microRNAs and Risk of Ischemic Stroke in a Chinese Population

Ischemic stroke is considered to be a complex disease consisting of a group of heterogeneous disorders with multiple genetic and environmental risk factors. MicroRNAs participated in various physiopathological processes; common single-nucleotide polymorphisms (SNPs) in pre-miRNAs have been shown to be associated with susceptibility to several human diseases. We evaluated the associations of the hsa-mir-196-a2/rs11614913 T/C, hsa-mir-146a/rs2910164 C/G, and hsa-mir-499/rs3746444 A/G polymorphisms in pre-miRNAs with the risk of ischemic stroke in a Chinese population. The three polymorphisms were identified in 296 ischemic stroke patients and 391 healthy controls using polymerase chain reaction–restriction fragment length polymorphism. The frequency of the allele G of hsa-mir-499/rs3746444 A/G showed significant association with ischemic stroke when compared with controls (OR?=?1.509, 95%CI?=?1.151–1.978, P?=?0.003). Increased ischemic stroke risks were associated with rs3746444 A/G genotypes in different genetic model (homozygote comparison: P?=?0.045, OR?=?2.084, 95%CI?=?1.019–4.262; heterozygote comparison: P?=?0.024, OR?=?1.489, 95%CI?=?1.063–2.087; dominant genetic model: P?=?0.007, OR?=?1.563, 95%CI?=?1.135–2.153). Similar results were obtained by adjusted fully risk factors. However, we failed to find any association between the alleles and genotypes of rs2910164 C/G and rs11614913 T/C SNPs and ischemic stroke, respectively (p?>?0.05). The present study provided evidence that hsa-mir-499/rs3746444 A/G polymorphism might be associated with a significantly increased risk of ischemic stroke in a Chinese population, indicating that the common genetic polymorphism in pre-microRNAs contributed to the pathogenesis of ischemic stroke.     

SNCA,MAPT, and GSK3B in Parkinson disease: a gene–gene interaction study

Background and purpose: Recent evidence suggests that variation in the SNCA, MAPT, and GSK3B genes interacts in affecting risk for Parkinson disease (PD). In the current study, we attempt to validate previously published findings, evaluating gene–gene interactions between SNCA, MAPT, and GSK3B in association with PD. Methods: Three Caucasian PD patient–control series from the United States, Ireland, and Norway (combined n = 1020 patients and 1095 controls) were genotyped for SNCA rs356219, MAPT H1/H2‐discriminating SNP rs1052553, and GSK3B rs334558 and rs6438552. Results: Our findings indicate that as previously reported, the SNCA rs356219‐G allele and MAPT rs1052553 (H1 haplotype) were both associated with an increased risk of PD, whilst contrary to previous reports, GSK3B variants were not. No pair‐wise interaction was observed between SNCA, MAPT, and GSK3B; the risk effects of SNCA rs356219‐G and MAPT rs1052553‐H1 were seen in a similar manner across genotypes of other variants, with no evidence suggesting synergistic, antagonistic, or deferential effects. Conclusions: In the Caucasian patient–control series examined, risk for PD was influenced by variation in SNCA and MAPT but not GSK3B. Additionally, those three genes did not interact in determining disease risk.     

<Emphasis Type="Italic">TOX3</Emphasis> Variants Are Involved in Restless Legs Syndrome and Parkinson’s Disease with Opposite Effects

Parkinson’s disease (PD) and restless legs syndrome (RLS) may be clinically and/or etiologically related, yet this association is under debate. Single-nucleotide polymorphisms (SNPs) in the TOX3 gene locus were implicated in both RLS and PD genome-wide association studies (GWASs), suggesting a potential pleiotropy. Two case-control cohorts including 644 PD patients, 457 RLS patients, and 945 controls were genotyped for one known RLS-related SNP (rs3104767) and one PD-related SNP (rs4784226) in the TOX3 locus. The associations between genotype and PD and RLS risk were tested using multivariate regression models. The allele frequencies of RLS-related SNP rs3104767 in RLS patients and controls were 0.35 and 0.43, respectively (OR 0.70, p?=?0.0007). Regression model suggested that this association is derived by homozygous carriage of rs3104767 (adjusted p?=?0.008). A nominal association was observed for homozygous carriers of the rs3104767 SNP in PD (OR 1.62, 95% CI 1.05–2.54, p?=?0.034), i.e., with an opposite direction of effect on RLS and PD, but this was not significant after Bonferroni correction. However, data from published GWASs of RLS and PD, and from the PDgene database, further supported these inverse associations. Our results confirm the association between the TOX3 SNP rs3104767 and RLS and suggest that TOX3 variants are involved in both RLS and PD, but with different or even opposite effects. Studies in larger populations of different ethnicities are required to further refine the TOX3 locus is involved in RLS and PD.     

Association of rs2062323 in the TREM1 gene with Alzheimer's disease and cerebrospinal fluid-soluble TREM2

Introduction and aims

Genetic variations play a significant role in determining an individual's AD susceptibility. Research on the connection between AD and TREM1 gene polymorphisms (SNPs) remained lacking. We sought to examine the associations between TREM1 SNPs and AD.

Methods

Based on the 1000 Genomes Project data, linkage disequilibrium (LD) analyses were utilized to screen for candidate SNPs in the TREM1 gene. AD cases (1081) and healthy control subjects (870) were collected and genotyped, and the associations between candidate SNPs and AD risk were analyzed. We explored the associations between target SNP and AD biomarkers. Moreover, 842 individuals from ADNI were selected to verify these results. Linear mixed models were used to estimate associations between the target SNP and longitudinal cognitive changes.

Results

The rs2062323 was identified to be associated with AD risk in the Han population, and rs2062323T carriers had a lower AD risk (co-dominant model: OR, 0.67, 95% CI, 0.51–0.88, p = 0.0037; additive model: OR, 0.82, 95% CI, 0.72–0.94, p = 0.0032). Cerebrospinal fluid (CSF) sTREM2 levels were significantly increased in middle-aged rs2062323T carriers (additive model: β = 0.18, p = 0.0348). We also found significantly elevated levels of CSF sTREM2 in the ADNI. The rate of cognitive decline slowed down in rs2062323T carriers.

Conclusions

This study is the first to identify significant associations between TREM1 rs2062323 and AD risk. The rs2062323T may be involved in AD by regulating the expression of TREM1, TREML1, TREM2, and sTREM2. The TREM family is expected to be a potential therapeutic target for AD.     

Synergistic effect of two oxidative stress‐related genes (heme oxygenase‐1 and GSK3β) on the risk of Parkinson’s disease

Background: Oxidative stress is a central factor in the pathogenesis of Parkinson’s disease (PD). Heme oxygenase‐1 (HO‐1) is an antioxidant protein expressed in response to oxidative challenge, and its expression levels are inversely correlated with glycogen synthase kinase‐3β (GSK3β) activity. Underexpression of HO‐1 in concert with an upregulation of GSK3β would result in a less effective antioxidant response and might increase the risk of PD. Methods: We examined two functional polymorphism in the promoter regions of HO‐1 (?413, rs2071746) and GSK3β (?157, rs6438552) in a group of 251 Spanish patients with PD and 234 controls. Results: Subjects carrying both the HO‐1 (?413, rs2071746) TT genotype and the GSK3β (?157, rs6438552) TT genotype had a four times higher risk of developing PD than subjects without these genotypes (adjusted by age and sex OR = 4.12; 95% CI = 1.45–11.71; Bonferroni corrected P = 0.024). Conclusions: Considering synergistic effects between polymorphisms in oxidative stress‐related genes may help in determining the risk profile for PD.     

Genetic predisposition in anti‐LGI1 and anti‐NMDA receptor encephalitis

We performed a genome‐wide association study in 1,194 controls and 150 patients with anti‐N‐methyl‐D‐aspartate receptor (anti‐NMDAR, n = 96) or anti‐leucine‐rich glioma‐inactivated1 (anti‐LGI1, n = 54) autoimmune encephalitis. Anti‐LGI1 encephalitis was highly associated with 27 single‐nucleotide polymorphisms (SNPs) in the HLA‐II region (leading SNP rs2858870 p = 1.22 × 10^?17, OR = 13.66 [7.50–24.87]). Potential associations, below genome‐wide significance, were found with rs72961463 close to the doublecortin‐like kinase 2 gene (DCLK2) and rs62110161 in a cluster of zinc‐finger genes. HLA allele imputation identified association of anti‐LGI1 encephalitis with HLA‐II haplotypes encompassing DRB1*07:01, DQA1*02:01 and DQB1*02:02 (p < 2.2 × 10^?16) and anti‐NMDAR encephalitis with HLA‐I allele B*07:02 (p = 0.039). No shared genetic risk factors between encephalitides were identified. Ann Neurol 2018;83:863–869     

Association of the rs1611115 polymorphism in DBH gene with Parkinson’s disease: a meta-analysis

A meta-analysis was performed to assess the association between the dopamine beta-hydroxylase (DBH) rs1611115 genetic polymorphism and Parkinson’s disease (PD). A comprehensive search was conducted to identify all case–control or cohort studies. The fixed or random effect-pooled measure was selected on the basis of a homogeneity test among studies. Heterogeneity among studies was evaluated using the I². We performed sensitivity analyses to evaluate the robustness of the results. Publication bias was estimated using Egger’s linear regression test. Five case–control studies corresponded to the inclusion criteria comprising 3926 patients and 3542 controls which were included in the present meta-analysis. Our meta-analysis showed no significant association between DBH rs1611115 genetic polymorphism and risk of PD in the codominant (REM, OR?=?1.017, 95%CI?=?0.854–1.210), dominant (REM, OR?=?0.989, 95%CI?=?0.826–1.185), and recessive (REM, OR?=?1.007, 95%CI?=?0.657–1.542) models. Moreover, in the subgroup analysis based on region (Asia and Europe), no significant associations were observed in Asia or Europe. This meta-analysis suggests that the DBH rs1611115 genetic polymorphism might not be associated with PD.     

Association of miR-122, miR-124 miR-126 and miR-143 gene polymorphisms with ischemic stroke in the northern Chinese Han population

Abstract

Objectives: Single nucleotide polymorphisms (SNPs) in microRNA (miRNA) genes can have diverse functional consequence by affecting the processing and target selection of miRNA. Recent evidence indicates that miRNA play important roles in the pathogenesis of atherosclerosis, which is a major cause of ischemic stroke (IS). The aim of this study was to clarify whether genetic variations in four miRNA genes (miR-143 rs4705342, miR-122 rs17669, miR-126 rs4636297, and miR-124 rs531564) contribute to IS susceptibility.

Methods: A case-control study was used to explore miRNA genetic polymorphisms in 567 IS patients and 552 control subjects that were frequency matched by age and gender. We genotyped four SNPs using polymerase chain reaction/ligation detection reaction.

Results: The miR-126 gene rs4636297 polymorphism was associated with decreased small vessel stroke risk (GA vs. GG: odds ratio (OR)?=?0.62, p?=?.015; GA?+?AA vs. GG: OR?=?0.637, p?=?.018; A vs. G: OR?=?0.696, p?=?.033). Using logistic regression analysis, this significant association remained after adjusting for confounding risk factors (adjusted OR?=?0.626, 95% confidence interval (CI)?=?0.426–0.921). However, the three other miRNA (miR-143 rs4705342, miR-122 rs17669, and miR-124 r531564) were not associated with IS risk under allele or genotype, nor in different inheritance models. In addition, there were no significant associations with stroke subtypes for these three miRNA SNPs.

Conclusion: Our study suggests that the miR-126 gene rs4636297 polymorphism may play an important role in the pathogenesis of small vessel occlusive stroke in the northern Chinese Han population.     

Meta-analysis of the IL23R and IL12B polymorphisms in multiple sclerosis

Purpose: Polymorphisms in the genes encoding interleukin-23 receptor (IL23R) and the p40 subunit of IL-12/23 (IL12B) have been implicated in multiple sclerosis (MS) risk. However, results of different studies are inconsistent. Our aim was to perform a meta-analysis on this topic. Methods: We assessed two variants (rs10889677 and rs7517847) of IL23R and the A1188C polymorphism (rs3212227) of IL12B. Electronic databases (PubMed, Web of Science and Scopus) were searched for eligible studies published until September 2014. Odds ratio (OR) and 95% confidence interval (95% CI) were used to investigate the strength of association in dominant, recessive, homozygote and allelic comparison models. Results: Seven case–control studies with 2250 MS patients and 2320 controls were included in this meta-analysis. The pooled results showed no association of rs10889677 and rs7517847 with MS risk in any of the genetic models. Although the pooled analysis showed an association between rs3212227 and MS in all study subjects in dominant (OR = 0.81, 95% CI: 0.66–0.99, P_h = 0.480, P_z = 0.044) and allelic comparison (OR = 0.84, 95% CI: 0.72–0.98, P_h = 0.967, P_z = 0.030) models, subgroup analysis based on ethnicity did not suggest an association between rs3212227 and MS risk in Caucasians in any of the genetic models, and there was no association between rs3212227 and MS risk in an Asian group. Conclusions: The IL23R polymorphisms rs10889677, rs7517847, and the IL12B polymorphism rs3212227 are not associated with MS risk.