Association of PDE4B polymorphisms and schizophrenia in Northwestern Han Chinese

PDE4B Proposed as a High Myopia Susceptibility Gene in Chinese Population

Myopia is the most common cause of refractive error worldwide. High myopia is a severe type of myopia, which usually accompanies pathological changes in the fundus. To identify high myopia susceptibility genes, DNA-pooling based genome-wide association analysis was used to search for a correlation between single nucleotide polymorphisms and high myopia in a Han Chinese cohort (cases vs. controls in discovery stage: 507 vs. 294; replication stage 1: 991 vs. 1,025; replication stage 2: 1,021 vs. 52,708). Three variants (rs10889602T/G, rs2193015T/C, rs9676191A/C) were identified as being significantly associated with high myopia in the discovery, and replication stage. rs10889602T/G is located at the third intron of phosphodiesterase 4B (PDE4B), whose functional assays were performed by comparing the effects of rs10889602T/T deletion of this risk allele on PDE4B and COL1A1 gene and protein expression levels in the rs10889602T/T^del/del, rs10889602T/T^del/wt, and normal control A549 cell lines. The declines in the PDE4B and COL1A1 gene expression levels were larger in the rs10889602T/T deleted A549 cells than in the normal control A549 cells (one-way ANOVA, p < 0.001). The knockdown of PDE4B by siRNA in human scleral fibroblasts led to downregulation of COL1A1. This correspondence between the declines in rs10889602 of the PDE4B gene, PDE4B knockdown, and COL1A1 protein expression levels suggest that PDE4B may be a novel high myopia susceptibility gene, which regulates myopia progression through controlling scleral collagen I expression levels. More studies are needed to determine if there is a correlation between PDE4B and high myopia in other larger sample sized cohorts.

The relationship between common variants in the DPEP1 gene and the susceptibility and clinical severity of osteoarthritis

AIM

Previous studies have provided evidence linking the DPEP1 gene to the risk of osteoarthritis (OA) in Europeans. In this study, we aimed to examine the relationship between DPEP1 gene and the susceptibility and clinical severity of OA in a Chinese Han population.

METHODS

This study comprised two independent samples. For the discovery stage, 1022 patients with knee OA and 1864 controls were recruited. Fourteen tag single nucleotide polymorphisms (SNPs) covering the DPEP1 gene were selected and genotyped. Associated SNPs in the discovery data set were subsequently genotyped in the replication data set consisting of 826 hip OA cases and 1662 controls. Both genotypic and allelic genetic associations were tested. The relationship of significant SNPs to the expression of DPEP1 and its neighboring genes was examined using the GTEx database.

RESULTS

A nonsynonymous SNP, rs1126464, was determined to be associated with the disease status of OA in both the discovery and replication stages (odds ratio [OR] 0.75, 95% confidence interval [95% CI] 0.68-0.82, P = 7.16 × 10^-11 ). This SNP was further characterized as being significantly related to a higher Kellgren-Lawrence grade in OA patients (OR 0.64, 95% CI 0.55-0.74, P = 2.53 × 10^-9 ). According to the GTEx data, SNP rs1126464 was significantly related to the gene expression of 15 genes in multiple types of human tissues.

CONCLUSION

We reported a common DNA variant in the DPEP1 gene that contributes to the risk of OA, providing additional evidence that the DPEP1 gene plays a significant role in the pathological mechanisms of OA.

Common variants in LTBP3 gene contributed to the risk of hip osteoarthritis in Han Chinese population

Osteoarthritis (OA) is a common chronic joint disease affected by environmental and genetic factors. The LTBP3 gene may be involved in the occurrence and development of OA by regulating TGF-β activity and the TGF-β signaling pathway. A total of 2780 study subjects, including 884 hip OA cases and 1896 controls, were recruited. Nine tag single-nucleotide polymorphisms (SNPs) located within the LTBP3 gene region were selected for genotyping. Genetic association analyses were performed at both the genotypic and allelic levels. GTEx data were extracted to investigate the functional consequence of significant SNPs. SNP rs10896015 was significantly associated with the risk of hip OA at both the genotypic (P=0.0019) and allelic levels (P=0.0009). The A allele of this SNP was significantly associated with a decreased risk of HOA (OR [95%CI] = 0.79 [0.69–0.91]). This SNP was also significantly associated with the clinical severity of hip OA. SNP rs10896015 could affect the gene expression of 11 genes, including LTBP3, in multiple human tissues based on GTEx data. We obtained evidence for a genetic association between the LTBP3 gene and hip OA susceptibility and clinical severity based on Chinese Han populations. Our findings replicated the association signals reported by a recent genome-wide association study and deepen the basic understanding of osteoarthritis pathology.

Common variants in KCNK5 and FHL5 genes contributed to the susceptibility of migraine without aura in Han Chinese population

A recent genome-wide meta study suggested that rs67338227 in the FHL5 gene and rs10456100 in the KCNK5 gene are associated with migraine from 27 population-based cohorts excluding Chinese population. Given that migraine without aura (MO) is the most common subtype of migraine, our aim was to systematically investigate the relationship of common variants in FHL5 and KCNK5 genes with the susceptibility to MO and provide clues as to the nature of the mechanisms involved in the etiology of migraine. A total of 3306 subjects including 1042 patients with MO and 2264 controls were recruited for the discovery stage, and 2530 individuals including 842 patients with MO and 1688 controls for the replication stage. Twenty-two tag SNPs (7 from FHL5 and 15 from KCNK5) were selected for genotyping. Genetic associations were analyzed at both single-marker and haplotype levels. Potential functional consequences of the significant SNPs were analyzed using gene expression data obtained from the GTEx database. Two SNPs, rs10456100 (KCNK5, P = 9.01 × 10-9) and rs7775721 (FHL5, P = 6.86 × 10-13), were determined to be significantly associated with MO in the discovery sample and were then replicated in another sample. In the combined sample set, the T allele of both SNPs was significantly associated with the increased risk of MO. Significant eQTL signals were identified for both SNP rs10456100 and rs7775721. Our findings suggest that the T allele carriers of SNP rs10456100 and rs7775721 are at increased risk of migraine.

Gene Environment Interactions Between the COL9A1 Gene and Maternal Drinking of Alcohol Contribute to the Risk of Congenital Talipes Equinovarus

Background: Previous studies have indicated that both genetic and environmental factors contribute to the risk of congenital talipes equinovarus (CTEV). The COL9A1 gene encodes one of the three alpha chains of type IX collagen, which is a key collagen component of hyaline cartilage. Our study aimed to evaluate the effect of COL9A1 gene polymorphisms on susceptibility to CTEV in the Han Chinese population. Methods: A total of 2205 unrelated subjects comprising 692 CTEV patients and 1513 healthy controls were recruited. Demographic and characteristic information was collected, including maternal smoking and maternal drinking. Genetic association analyses and gene-environment interaction analyses were conducted based on the genotypic data of 36 tag single nucleotide polymorphisms (SNPs). Results: Although there was no association between genotyped SNPs and CTEV, a gene-environment interaction signal between SNP rs6455357 and maternal drinking was identified. Furthermore, significant heterogeneity was identified for this interaction signal when stratified by maternal drinking. For subjects with never maternal drinking, the A allele of SNP rs6455357 was significantly associated with a decreased risk of CTEV. In contrast, the A allele was associated with an increased risk of CTEV in the "occasional" and "often" groups. Conclusions: Our results indicate a combined effect of genetics and environmental factors on the etiology of CTEV. This study increases our understanding of the etiology of CETV and provides useful information for genetic counseling for at-risk families for the development of prevention programs and improved management.

Association of rs2862851 in TGFA Gene with Peripheral TGFA Levels and the Severity of Knee Osteoarthritis in the Han Chinese Population

Background: Osteoarthritis (OA) is a complex joint disorder characterized by sclerosis of subchondral bone. The knee is one of the most commonly affected joints. Given that the genetic mechanisms underlying knee OA remain elusive, our study aims were to first confirm the association of the TGFA gene alleles with the risk of knee OA and, second, to evaluate the relationship between peripheral TGFA concentrations and knee OA in an independent Han Chinese population. Materials and Methods: We performed a case-control study consisting of 392 knee OA patients and 808 unrelated healthy controls. Single-marker-based association analyses and haplotype-based analyses using 3 single nucleotide polymorphisms (SNPs) were performed to confirm the association of TGFA gene alleles with the risk of knee OA. Furthermore, we used enzyme-linked immunosorbent assay (ELISA) kits to detect the peripheral blood TGFA concentrations in patients and healthy controls and then evaluated the relationships between the TGFA alleles and genotypes with serum TGFA levels. Results: We replicated the genetic association of the rs2862851 T allele with the risk of knee OA (p = 1.68 × 10^-4, OR = 1.41). Moreover, we observed that the peripheral TGFA concentrations were higher in knee OA patients than in healthy controls (p = 8.15 × 10^-13). The peripheral TGFA concentrations were significantly different among the various rs2862851 genotypes for both cases (p = 4.16 × 10^-16) and controls (p = 7.24 × 10^-19). The individuals with the TT genotype in both cases and controls, had the highest peripheral TGFA concentrations. Moreover, with the increase in knee OA grade, peripheral TGFA concentration also increased (p = 1.36 × 10^-72). Conclusion: Our study confirmed the association of the TGFA gene with the risk of knee OA and identified a positive correlation between peripheral TGFA levels and the severity of knee OA in the Han Chinese population, providing clues for understanding the etiology of knee OA.

Evaluation of relationship between DNA methyltransferase 3 β gene and the risk of hip osteoarthritis: A case-control study based on a Han Chinese population

AIM

Osteoarthritis (OA) is a chronic degenerative joint disease. Early studies have indicated that genetic and environmental factors contribute to the risk of OA. However, the etiology of OA remains unknown. Our study aimed to evaluate the association of DNMT3B gene with the risk of hip OA in Han Chinese individuals.

METHODS

A total of 2070 subjects were recruited into the study, including 658 patients with hip OA and 1412 healthy controls. Twelve tag single nucleotide polymorphisms (SNPs) were selected and genotyped in our samples. Genetic associations between DNMT3B gene and the risk of hip OA were examined at both the single marker and haplotype levels. Cis-expression quantitative trait loci signals that achieve genome-wide significance of targeted SNPs from multiple types of human tissues were extracted from the GTEx database.

RESULTS

Significant signals were identified for SNP rs2424905 in 4 genetic models. The T allele was significantly associated with an increased risk of hip OA (odds ratio = 1.53; 95% CI = 1.28-1.83). The T allele was also significantly associated with higher Kellgren-Lawrence grade in the patients with hip OA (χ2  = 32.70, P = 1.37 × 10-6 ). Moreover, SNP rs2424905 was significantly associated with the gene expression level of multiple genes, including DNMT3B, C20orf203, COMMD7, EFCAB8, MAPRE1, and RP5-1085F17.3, from several types of human tissues.

CONCLUSION

Our results indicated that rs2424905 of DNMT3B gene contributed to the risk of hip OA and its clinical severity in a Han Chinese population. These findings suggested that rs2424905 of DNMT3B could be a promising genetic marker to assess susceptibility to hip OA in Han Chinese populations.

The effects of common variants in MDM2 and GNRH2 genes on the risk and survival of osteosarcoma in Han populations from Northwest China

Accumulating evidence has shown that both MDM2 and GNRH2 might be related to Osteosarcoma (OS) susceptibility. The study aimed to evaluate the effects of common variants in MDM2 and GNRH2 genes on the risk and survival of osteosarcoma in Han populations from Northwest China. In the study, we recruited 2292 subjects including 596 OS patients and 1696 healthy controls and genotyped 16 selected tag SNPs (6 from GNRH2 and 10 from MDM2). Genetic association analyses were performed at the genotypic and allelic levels. Survival curves were made for OS patients with different genotypes. Two SNPs, rs1690916 (MDM2, P = 0.0002) and rs3761243 (GNRH2, P = 0.0004), were identified to be significantly associated with OS risk. Moreover, SNP rs3761243 was strongly associated with pathological fracture (P = 2.61 × 10^–14), metastasis (P < 2.2 × 10^–16), and Enneking stage (P < 2.2 × 10^–16) in the OS group. Furthermore, survival curves based on different genotypes of SNP rs3761243 were found to be significantly different (P = 0.0003), suggesting increased risk with more copies of C alleles. Our results provide supportive evidence for genetic associations of MDM2 and GNRH2 genes with susceptibility to OS, and for the positive correlation of SNP rs3761243 in GNRH2 with the survival status of OS patients in Han populations from Northwest China.

SAP30BP gene is associated with the susceptibility of rotator cuff tear: a case-control study based on Han Chinese population

Background

Multiple studies have indicated that genetic components contribute significantly to the risk of rotator cuff tears. Previous studies have suggested that the SAP30BP gene may play an essential role in the development of rotator cuff tears. The aim of this study was to evaluate the potential association of the SAP30BP gene with the susceptibility to rotator cuff tears in a Han Chinese population.

Methods

A total of 394 patients with rotator cuff tears and 998 healthy controls were included in the study. Twelve tag single nucleotide polymorphisms (SNPs) located in the region of the SAP30BP gene were selected for genotyping. Genetic association analyses were performed using χ² tests for each SNP. Significant associations were searched in the GTEx database for their functional consequences.

Results

SNP rs820218 was significantly associated with rotator cuff tears (χ² = 9.49, P = 0.0021, OR [95% CI] = 0.67 [0.52–0.87]). In addition, SNP rs820218 was found to be significantly associated with the gene expression level of SAP30BP in whole blood (NES = 0.12, P = 1.00 × 10⁻⁶).

Conclusion

Our study has shown that the genetic polymorphism of SAP30BP contributes to the risk of rotator cuff tears in Chinese Han people. Individuals with the A allele for SNP rs820218 were less susceptible to developing rotator cuff tears.

Common Variants in the ARG1 Gene Contribute to the Risk of Dilated Cardiomyopathy in the Han Chinese Population

Background: Arginase I, encoded by the ARG1 gene, is an enzyme that catalyzes the conversion of arginine to ornithine in the urea cycle; mutations in this gene has recently been reported to be associated with dilated cardiomyopathy (DCM) in Pakistan. The present study aimed to investigate the relationship between ARG1 gene mutations and DCM in the Han Chinese population. Methods: A total of 488 DCM cases and 924 matched-healthy controls were recruited. All subjects were genotyped for 12 tag single nucleotide polymorphisms (SNPs) within the ARG1 gene. Genetic association studies, including SNP and haplotype analyses, were performed. Further analyses were conducted to examine the correlations between the associated SNPs and specific clinical characteristics. Results: Only the rs2781666 and rs2781667 loci in the ARG1 gene were found to be significantly associated with DCM compared to the healthy controls. The risk of DCM at both of these loci for T allele carriers was ∼1.42-fold higher than that for carriers of the alternative alleles. There were significant differences in end-diastolic interventricular septal diameter, end-diastolic left ventricular posterior wall diameter, left ventricular end-diastolic diameter, left ventricular end-systolic diameter, and left ventricular ejection fraction among the genotype distributions of both SNPs. Furthermore, we found that the T alleles at the rs2781666 and rs2781667 loci were significantly associated with DCM in gender subgroups and the subgroup of patients <58 years of age. The haplotype T-T (rs2781666-rs2781667) also showed a significant association with DCM. Conclusion: Our results support the hypothesis that alleles and haplotypes of the ARG1 gene are significantly involved in the etiology of DCM in the Han Chinese population, but further research is necessary to elucidate the mechanism governing this association.

Evaluation of genetic susceptibility of common variants in SOX9 in patients with congenital talipes equinovarus in the Han Chinese population

Background

Congenital talipes equinovarus (CTEV) is a common birth defect that causes severe deformities of one or both feet. Genetics have been proven to play a key role in the risk of CTEV. Our study aimed to evaluate the genetic susceptibility of common variants in the SOX9 gene to CTEV in a Han Chinese population.

Methods

In this study, we recruited 2,205 study participants, including 692 CTEV patients and 1513 healthy controls. A total of seven selected single-nucleotide polymorphisms (SNPs) within the SOX9 gene were genotyped, and environmental variables, including maternal smoking and alcoholic drinking habits, were assessed. In addition, bioinformatics analyses were performed to explore the potential biological functions of the associated SNPs.

Results

The SNP rs73354570 was identified to be significantly associated with the risk of CTEV (OR = 1.53, P = 2.11 × 10⁻⁵), and the C allele was associated with an increased risk of CTEV. A dose-dependent pattern could be observed in genotypic analyses. The OR for individuals with AC genotypes was 1.37 (95% CI 1.09–1.71), and the OR for individuals with CC homozygotes was 1.47 (95% CI 1.18–1.82). Further analyses identified that rs73354570 is located within a region of multiple binding proteins, including CEBPB and POLR2A, which suggested that this SNP was also part of genetic motifs that are found within several cell types.

Conclusion

Our results provide evidence supporting the important role of the SOX9 gene in the contribution to the risk of CTEV.

The Effect of Common Variants in SLC44A2 on the Contribution to the Risk of Deep Cein Thrombosis after Orthopedic Surgery

Aim: Deep vein thrombosis (DVT) is a common complication of orthopedic surgery. Multiple lines of evidence indicate that genetic factors play an important role in the development of DVT following orthopedic surgery (DVTFOS). Recent evidence suggested that the solute carrier family 44 member 2 (SLC44A) gene may contribute to the risk of DVT. In this study, we aimed to investigate the associations of SLC44A2 and DVTFOS in Chinese Han individuals.

Methods: In the study, 2,655 subjects, including 689 DVTFOS patients and 1,966 controls, were recruited. Eighteen SNPs were genotyped in the study. Genetic association analyses were performed at both the single marker and haplotype levels. Bioinformatics analyses were conducted to predict the functional consequences of significant SNPs.

Results: SNP rs2288904 of SLC44A2 was identified as being significantly associated with DVTFOS (P = 0.0003, OR [95%CI]= 1.28[1.12–1.46]). Allelic analyses showed that the G allele of this SNP significantly elevated the risks of DVTFOS, which was replicated in the genotypic association analyses. Moreover, a two-SNP haplotype, including rs2288904, was found to be strongly correlated with the risk of DVTFOS (P = 4.15 × 10⁻¹¹). Widespread effects in the expression quantitative trait loci were identified for rs2288904 in multiple tissues.

Conclusion: In summary, our results provide further supportive evidence of the association of SLC44A2 with the risk of DVTFOS, which also provide clues for understanding the important roles of the SLC44A2 gene in the pathogenesis of DVTFOS and in the development of preventive strategies.

Association Between Genetic Polymorphisms of CR2 Gene and the Risk of Steroid-Induced Osteonecrosis of the Femoral Head in the Chinese Han Male Population

Background: Multiple lines of evidence have suggested that genetic factors may contribute to steroid-induced osteonecrosis of the femoral head (SONFH). Complement receptor 2 (CR2), constituting a family of regulators of complement activation, has been recently reported to be associated with osteonecrosis of the femoral head (ONFH) in Koreans. The aim of this study was to evaluate the relationships between polymorphisms of the CR2 gene and susceptibility to SONFH in the male Han Chinese population. Materials and Methods: A total of 468 SONFH patients and 1224 healthy controls were recruited for this study. Ten tag single nucleotide polymorphisms (SNPs) located within the CR2 gene were genotyped. Genetic association analyses, including SNP and haplotypic analyses, were performed for the 10 SNPs. Furthermore, bioinformatic analyses were conducted to examine the functional consequences of SNPs shown to be significantly associated with SONFH. Results: An intronic SNP, rs311306, was identified to be significantly associated with the risk of SONFH (p = 0.0008, odds ratio = 1.44). Allelic analyses showed that the C allele of this SNP significantly elevated the risk of SONFH, which was replicated in genotypic association analyses. Moreover, a 3-SNP haplotype was significantly associated with SONFH (rs311306-rs17044576-rs3767933, p = 7.49 × 10^-8). Furthermore, bioinformatic analyses indicated limited functional consequences of SNP rs311306, but a complex interaction network was constructed for the protein encoded by the SLC44A2 gene and proteins encoded by the CD19, CD81, and C3 genes. Conclusion: Our findings shed new light on the link between the CR2 gene and SONFH in Han Chinese males, providing clues as to the nature of the mechanisms involved in the etiology of ONFH.

Evaluation of Common Variants in the AKNA Gene and Susceptibility to Knee Osteoarthritis Among the Han Chinese

Background: Osteoarthritis (OA) is a complex degenerative joint disease that is associated with both genetic and environmental factors. The AKNA gene, located at 9q32, has recently been identified as being associated with knee osteoarthritis (KOA) in the Mexican population. Our aim was to investigate the relationship of common variants in this gene with the risk of KOA in a large Han Chinese population. Methods: A total of 2,500 Han Chinese subjects were recruited, consisting of 824 KOA patients and 1,676 controls. Eight tag single nucleotide polymorphisms (SNPs) located within the ANKA gene were selected for genotyping. Single marker-based association analyses were conducted using multiple modes of inheritance, including genotypic, allelic, dominant, and recessive. Haplotype-based association analyses were also performed. Plink was utilized for genetic association analyses. In addition, we examined the GTEx database to test the expression quantitative loci effects of the significant SNPs within the AKNA gene. Results: Among these eight SNPs evaluated we identified one, rs10817595, as being significantly associated with the risk of KOA. Compared to the CC genotype at this locus, the odds ratio (95% confidence interval) for KOA with the AA genotype was 1.58 (1.23-2.01)-fold greater. A linkage disequilibrium block that included this SNP was also determined to be significantly associated with the risk of KOA (χ² = 25.08, p = 3.58 × 10^-6). In general, the minor allele A of SNP rs10817595 was associated with an increased risk of KOA. Conclusion: This study is the first to present evidence for a potential link between the risk of KOA and an AKNA gene polymorphism among persons with a Han Chinese ancestry. Future functional analyses based on animal models and sequencing-based population studies are needed to elucidate the biological plausibility and genetic architecture of AKNA for KOA susceptibility.

Discovery, Radiolabeling, and Evaluation of Subtype-Selective Inhibitors for Positron Emission Tomography Imaging of Brain Phosphodiesterase-4D

We aimed to develop radioligands for PET imaging of brain phosphodiesterase subtype 4D (PDE4D), a potential target for developing cognition enhancing or antidepressive drugs. Exploration of several chemical series gave four leads with high PDE4D inhibitory potency and selectivity, optimal lipophilicity, and good brain uptake. These leads featured alkoxypyridinyl cores. They were successfully labeled with carbon-11 (t_1/2 = 20.4 min) for evaluation with PET in monkey. Whereas two of these radioligands did not provide PDE4D-specific signal in monkey brain, two others, [¹¹C]T1660 and [¹¹C]T1650, provided sizable specific signal, as judged by pharmacological challenge using rolipram or a selective PDE4D inhibitor (BPN14770) and subsequent biomathematical analysis. Specific binding was highest in prefrontal cortex, temporal cortex, and hippocampus, regions that are important for cognitive function. [¹¹C]T1650 was progressed to evaluation in humans with PET, but the output measure of brain enzyme density (V_T) increased with scan duration. This instability over time suggests that radiometabolite(s) were accumulating in the brain. BPN14770 blocked PDE4D uptake in human brain after a single dose, but the percentage occupancy was difficult to estimate because of the unreliability of measuring V_T. Overall, these results show that imaging of PDE4D in primate brain is feasible but that further radioligand refinement is needed, most likely to avoid problematic radiometabolites.

Genetic Polymorphisms on 4q21.1 Contributed to the Risk of Hashimoto's Thyroiditis

Background: Hashimoto's thyroiditis (HT) is a common autoimmune disease characterized by lymphoid infiltration of the thyroid gland, including both T- and B-cells. Early studies have shown that HT is a complex disorder affected by both environmental and genetic factors. Recently, the single nucleotide polymorphism (SNP) rs2276886 associated with the CXCL9 gene was identified as associated with autoimmune thyroid disease susceptibility in Japanese populations. The aim of the present study was to validate this result for HT in a Chinese Han population. Methods: Study subjects, including 688 HT cases and 1456 healthy controls, were recruited, and 10 SNPs located within the CXCL9 gene were genotyped. Genetic association analyses were performed by fitting logistic models. Bioinformatics tools, including RegulomeDB and GTEx were utilized to investigate the functional consequences of the SNPs found to be significantly associated with HT. Results: SNP rs2276886 was identified as significantly associated with the risk of HT (odds ratio [OR] = 1.25, p = 0.0006). No significant expression quantitative trait loci (eQTL) signals could be identified for CXCL9. Significant eQTL signals were found for other genes, including ART3, CXCL10, CXCL11, NAAA, PPEF2, and SCARB2. This SNP physically maps to the CXCL9 gene region; however, further bioinformatic analyses indicated that this SNP might be associated with the gene NAAA. Conclusions: The rs2276886 SNP was found to be significantly associated with HT susceptibility. However, our findings suggest that this SNP which maps to the chromosomal region 4q21.1 likely effects the NAAA gene (as opposed to the CXCL9 gene), but still contributes to the susceptibility to HT in Han Chinese populations.

PDE4B gene polymorphism in Russian patients with panic disorder

Background

Panic disorder is a complex disease of unclear etiology but with an apparent genetic component. PDE4B gene product is involved in many cell processes owing to its function-regulation of the level of a second messenger cAMP. PDE4B gene polymorphism has been shown to be associated with some mental disorders including panic disorder.

Aims

The goal of our study was to evaluate the role of 3 SNPs in the PDE4B gene in the development of panic disorder.

Methods

94 patients diagnosed with panic disorder according to the DSM-IV criteria were enrolled in the study. The population control group included 192 subjects. Genotyping was carried out by real-time PCR with TaqMan probes.

Results

The investigated substitutions are not associated with panic disorder in general and in female/male cohorts (p > 0.05). The analysis of complex genotypes demonstrated two protective complex genotypes (rs1040716:A, T + rs10454453:A + rs502958:A and rs1040716:A, T + rs502958:A) associated with panic disorder in general regardless of the patient's gender (p < 0.05). These genotypes did not correlate with the patient's sex.

Conclusions

We found two complex protective genotypes associated with panic disorder. This can be due to the fact that predisposition to the disease are associated with other genes, while PDE4B gene polymorphism reduces their effect.

Evaluation of the Relationship Between Common Variants in the TLR-9 Gene and Hip Osteoarthritis Susceptibility

Objective: Hip osteoarthritis (HOA) is one of the most common types of osteoarthritis and affects nearly 10% of men and 18% of women who are >60 years of age worldwide. It has been demonstrated to be a genetic disease with a 50% heritability risk. Recently, the TLR-9 gene has been associated with knee OA in both Turkish and Chinese populations, but the relationship between the TLR-9 gene and HOA has not been evaluated. In this study, we aimed to evaluate the relationship between the common genetic variants in the TLR-9 gene and the predisposition of Han Chinese individuals to HOA. Methods: A total of 730 HOA patients and 1220 healthy controls were recruited in a hospital-based case-control study. Six common single nucleotide polymorphisms (SNPs) of the TLR-9 gene were selected for genotyping, and genetic association analyses were performed using both single-marker and haplotype-based methods. Results: The SNP rs187084 was found to be significantly associated with the risk of HOA after a Bonferroni correction (adjusted allelic p-values with age, gender, and body mass index [BMI] = 0.0008). The results indicated that the A allele of rs187084 is a risk allele for HOA and is likely to be a predisposing factor leading to an increased risk of HOA (adjusted odds ratio with age, gender, and BMI = 1.26, 95% confidence interval = 1.10-1.43). The results of the haplotype analyses confirmed a similar pattern to the SNP analyses. Conclusions: Our study provides strong evidence that variations in the TLR-9 gene are closely linked with genetic susceptibility to HOA in the Han Chinese population. This finding furthers the role of TLR-9 in the development and occurrence of OA in general.

Relationship Between Genetic Polymorphisms of the TNF Gene and Hallux Valgus Susceptibility

Background: Hallux valgus (HV) is a type of forefoot deformity affecting ∼23% of adults. Previous studies have shown that HV is highly heritable. Tumor necrosis factor (TNF) is an important proinflammatory cytokine involved in bone remodeling and plays essential roles in osteoarthritis and chronic inflammatory bone diseases, including HV. Methods: A total of 1,788 Chinese women comprising 637 HV subjects and 1,151 controls were recruited. Twelve single nucleotide polymorphisms (SNPs) located in TNF and its promoter regions were selected and genotyped. Genetic association analyses were performed to investigate potential susceptibility SNPs. Bioinformatic and expression quantitative trait loci (eQTL) analyses were conducted to examine the functional consequences of the SNPs identified as being significantly associated with HV. Results: SNP rs1800629, which is located at the 5' end of the promoter region of TNF, was identified as significantly associated with HV status in Chinese women (OR = 0.56, p = 2.12 × 10^-6). Bioinformatic analyses using RegulomeDB indicated that this SNP has important functional significance, but subsequent eQTL analyses did not identify a significant association between rs1800629 and TNF gene expression. In addition, 26 genes with cis-eQTL for rs1800629 were identified. Conclusions: This study identified a susceptibility SNP for HV located within the promoter region of the TNF gene. Bioinformatic and eQTL analyses linked this SNP to 26 genes but not to TNF. Functional studies are needed to more fully characterize the effects of this SNP.

Genetic Association of Phosphodiesterases With Human Cognitive Performance

Recent, large-scale, genome-wide association studies (GWAS) provide a first view of the genetic fine structure of cognitive performance in healthy individuals. These studies have pooled data from up to 1.1 million subjects based on simple measures of cognitive performance including educational attainment, self-reported math ability, highest math class taken, and pooled, normalized scores from cognitive tests. These studies now allow the genome-wide interrogation of genes and pathways for their potential impact on human cognitive performance. The phosphodiesterase (PDE) enzymes regulate key cyclic nucleotide signaling pathways. Many are expressed in the brain and have been the targets of CNS drug discovery. Genetic variation in PDE1C, PDE4B and PDE4D associates with multiple measures of human cognitive function. The large size of the human PDE4B and PDE4D genes allows genetic fine structure mapping to transcripts encoding dimeric (long) forms of the enzymes. Upstream and downstream effectors of the cAMP pathway modulated by PDE4D [adenylate cyclase 1 (ADCY1), ADCY8, PRKAR1A, CREB1, or CREBBP] did not show genetic association with cognitive performance, however, genetic association was seen with brain derived neurotrophic factor (BDNF), a gene whose expression is modulated by cAMP. Notably absent was genetic association in healthy subjects to targets of CNS drug discovery designed to improve cognition in disease states by the modulation of cholinergic [acetylcholinesterase (ACHE), choline acetyltransferase (CHAT), nicotinic alpha 7 acetylcholine receptor (CHRNA7)], serotonergic (HTR6), histaminergic (HRH3), or glutamatergic (GRM5) pathways. These new data provide a rationale for exploring the therapeutic benefit of selective inhibitors of PDE1C, PDE4B and PDE4D in CNS disorders affecting cognition.

Relationship of common variants in Interleukin 33 gene with susceptibility and prognosis of osteosarcoma in Han Chinese population

Osteosarcoma (OS) is one of the most common malignant bone tumors. Many previous studies have indicated that OS is a complex disease and that its development may be affected by multiple genetic factors, which may contribute to its carcinogenesis. The aim of the present study was to evaluate the relationship of IL-33 with susceptibility and prognosis of OS in Han Chinese individuals. A total of 1,605 study subjects including 507 OS patients and 1,098 controls were recruited. Eighteen SNPs mapped to IL-33 were selected for genotyping. Genetic associations between selected SNPs and OS disease status were evaluated. Survival analyses, including Kaplan-Meier analysis and Cox model fitting for significant SNPs, were performed. The functional consequences of significant SNPs were analyzed using a publicly available database. SNP rs1048274 was identified to be significantly associated with OS disease status (OR=0.75, P=1.53×10-4). Compared to the GA and GG groups, OS patients with the AA genotype of rs1048274 had better survival rate. The hazard ratio of SNP rs1048274 (AA group compared to GG+GA group) was 0.35 (95% confidence interval of 0.25-0.5) following adjustment for several clinical variables. In conclusion, our results suggested that IL-33 may play a key role in the etiology of OS, indicating IL-33 as a potential genetic risk factor of the development and prognosis of OS.

Genetic effects of BDKRB2 and KNG1 on deep venous thrombosis after orthopedic surgery and the potential mediator

Deep venous thrombosis (DVT) is a common complication of orthopedic surgery. Genetic risk factors and high heritability carried a substantial risk of DVT. In this study, we aimed to investigate the potential association in the Han Chinese population between the polymorphisms of BDKRB2 and KNG1 and DVT after orthopedic surgery (DVTAOS). A total of 3,010 study subjects comprising 892 DVT cases and 2,118 controls were included in the study, and 39 single nucleotide polymorphisms (SNPs) in total (30 for BDKRB2 and 9 for KNG1) were chosen for genotyping. Two SNPs, rs710446 (OR = 1.27, P = 0.00016) and rs2069588 (OR = 1.29, P = 0.00056), were identified as significantly associated with DVTAOS. After adjusting for BMI, the significance of rs2069588 decreased (P = 0.0013). Haplotype analyses showed that an LD block containing rs2069588 significantly correlated with the DVTAOS risk. Moreover, bioinformatics analysis indicated that hsa-miR-758-5p and BDKRB2 formed miRNA/SNP target duplexes if the rs2069588 allele was in the T form, suggesting that rs2069588 may alter BDKRB2 expression by affecting hsa-miR-758-5p/single-nucleotide polymorphism target duplexes. Our results demonstrate additional evidence supporting that there is an important role for the KNG1 and BDKRB2 genes in the increased susceptibility of DVTAOS.

Relationship of WNT4 Gene with the Risk of Epithelial Ovarian Cancer: A Han Chinese Population-Based Association Study

OBJECTIVE

In China, epithelial ovarian cancer (EOC) patients account for the majority of ovarian cancer patients. The pathogenesis of EOC, one of the most lethal gynecological malignancies, remains unclear. Recently, the role of WNT4 in gynecological disease and tumor development was reported, and a suspicious association of WNT4 with EOC was identified in Europeans. However, the contributions of the WNT4 gene to EOC and the underlying molecular mechanisms remains largely unknown. To determine whether the WNT4 gene is associated with EOC, this study investigated polymorphisms of the WNT4 gene in Han Chinese individuals.

MATERIALS AND METHODS

We designed a case/control study with 707 EOC patients and 1563 unrelated healthy controls of Han Chinese descent. A total of eight tag single-nucleotide polymorphisms (SNPs) were genotyped successfully, and both single SNP and haplotype analyses were performed to detect the potential association of variations in the WNT4 gene with EOC.

RESULTS

The SNP rs56318008 was found to be strongly associated with EOC risk. In the serous EOC subgroup, individuals harboring the T allele of rs56318008 exhibited a higher risk of EOC than individuals harboring the C allele. Moreover, the odds ratios and 95% confidence intervals revealed an increased risk of EOC in individuals with the T allele of the SNP, and haplotypic analyses confirmed the results, showing a similar pattern.

CONCLUSION

Our results show that the WNT4 gene is associated with EOC risk, indicating that this gene may be a potential genetic risk factor for developing EOC.

Voltage-gated calcium channel activity and complex related genes and schizophrenia: A systematic investigation based on Han Chinese population

Schizophrenia (SCZ) is a devastating mental disorder affecting approximately 1% of the worldwide population. Early studies have indicated that genetics plays an important role in the onset and development of SCZ. Accumulating evidence supports that SCZ is linked to abnormalities of synapse transmission and synaptic plasticity. Voltage-gated calcium channel (VGCC) subunits are critical for mediating intracellular Ca^2 + influx and therefore are responsible for changing neuronal excitability and synaptic plasticity. To systematically investigate the role of calcium signaling genes in SCZ susceptibility, we conducted a case-control study that included 2518 SCZ patients and 7521 healthy controls with Chinese Han ancestry. Thirty-seven VGCC genes, including 363 tag single nucleotide polymorphisms (SNPs), were examined. Our study replicated the following previously identified susceptible loci: CACNA1C, CACNB2, OPRM1, GRM7 and PDE4B. In addition, several novel loci including CACNA2D1, PDE4D, NALCN, and CACNA2D3 were also identified to be associated with SCZ in our Han Chinese sample. Combined with GTEx eQTL data, we have shown that CASQ2, ITGAV, and TMC2 can be also added into the prioritization list of SCZ susceptible genes. Two-way interaction analyses identified widespread gene-by-gene interactions among VGCC activity and complex-related genes for the susceptibility of SCZ. Further sequencing based studies are still needed to unravel potential contributions of schizophrenia risk from rare or low frequency variants of these candidate genes.

Relationship of common variants in VEGFA gene with osteonecrosis of the femoral head: A Han Chinese population based association study

The pathology of non-traumatic osteonecrosis of the femoral head (ONFH) is complex. Several studies have linked some polymorphisms of vascular endothelial growth factors A (VEGFA) with ONFH, but the results are not consistent and are even conflicting. In the study, 22 single nucleotide polymorphisms (SNPs) in VEGFA were genotyped in 1,762 subjects (489 cases and 1,273 controls). Genetic association analyses were performed in single markers and haplotype levels. Stratification analysis was conducted for ONFH patients. Gene by environment interactions were tested between VEGFA and the smoking status of the subjects. Gene expression and eQTL data of significant SNPs were extracted from GTEx to examine their potential biological function. The SNP, rs2010963, was identified to be significantly associated with ONFH (χ² = 11.66, P = 0.0006, OR = 1.29). Haplotypes including rs2010963 were also identified to be correlated with ONFH in the haplotype-based analyses. After stratifying by the causes of ONFH, a significant signal from rs2010963 could only be identified in alcohol-induced patients (P_allelic = 0.0009) but not in steroid-induced patients (P_allelic = 0.055). No significant results were obtained from the gene by environmental interaction analyses. Significant expression differences of VEGFA were identified in multiple human tissues for different genotypes of rs2010963. Our findings indicate that SNP rs2010963 is significantly associated with ONFH.

Evaluation of Common Variants in Matrix Metalloproteinase-9 Gene with Lumbar Disc Herniation in Han Chinese Population

OBJECTIVE

Lumbar disc herniation (LDH) is a common and frequent orthopedic disease with strong genetic determinants. The disruption of the intervertebral disc extracellular matrix has been found to play a key role in the development of LDH, suggesting that abnormal matrix metalloproteinases (MMPs) may promote the degradation of the disc matrix. MMP-9, an important member of the MMP family, is a good candidate for the LDH susceptibility gene. The present study aimed to investigate the association of common variants in the MMP-9 gene with the risk, severity, and clinical characteristic variables of LDH.

MATERIALS AND METHODS

Fourteen tag single nucleotide polymorphisms (SNPs) entirely covering the region of the MMP-9 gene were analyzed in a sample of 845 patients and 1751 healthy controls.

RESULTS

The SNP rs17576 was found to be significantly associated with susceptibility to LDH (OR = 0.77, p = 0.0002), which was also confirmed by haplotype-based analyses (rs79845319-rs17576-rs45437897, global p < 0.001). Our results indicated that the A allele of rs17576 reduced the risk of LDH by ∼23% on average. Furthermore, the G allele of rs17576 was found to correlate with more severe grades of disc degeneration.

CONCLUSION

Our results provide additional evidence supporting an important role of the MMP-9 gene in the pathogenesis of LDH.

Genetic susceptibility of postmenopausal osteoporosis on sulfide quinone reductase-like gene

Postmenopausal osteoporosis is a major health problem with important genetic factors in postmenopausal women. We explored the relationship between SQRDL and osteoporosis in a cohort of 1006 patients and 2027 controls from Han Chinese postmenopausal women. Our evidence supported the significant role of SQRDL in the etiology of postmenopausal osteoporosis.

INTRODUCTION

Postmenopausal osteoporosis (PMOP) is a metabolic bone disease leading to progressive bone loss and the deterioration of the bone microarchitecture. The sulfide-quinone reductase-like protein is an important enzyme regulating the cellular hydrogen sulfide levels, and it can regulate bone metabolism balance in postmenopausal women. In this study, we aimed to investigate whether SQRDL is associated with susceptibility to PMOP in the Han Chinese population.

METHODS

A total of 3033 postmenopausal women, comprised of 1006 cases and 2027 controls, were recruited in the study. Twenty-two SNPs were selected for genotyping to evaluate the association of SQRDL gene with BMD and PMOP. Association analyses in both single marker and haplotype levels were performed for PMOP. Bone mineral density (BMD) was also utilized as a quantitative phenotype in further analyses. Bioinformatics tools were applied to predict the functional consequences of targeted polymorphisms in SQRDL.

RESULTS

The SNP rs1044032 (P = 6.42 × 10^-5, OR = 0.80) was identified as significantly associated with PMOP. Three SNPs (rs1044032, rs2028589, and rs12913151) were found to be significantly associated with BMD. Although limited functional significance can be obtained for these polymorphisms, significant hits for association with PMOP were found. Moreover, further association analyses with BMD identified three SNPs with significantly independent effects.

CONCLUSIONS

Our evidence supported the significant role of SQRDL in the etiology of PMOP and suggest that it may be a genetic risk factor for BMD and osteoporosis in Han Chinese postmenopausal women.

Genetic polymorphisms of GZMB and vitiligo: A genetic association study based on Chinese Han population

Vitiligo is a skin disease that affects 1% of the population worldwide. Both environmental and genetic factors contribute to the risk of vitiligo. GZMB encodes the enzyme Granzyme B, which plays an important role in cytotoxic T cell-induced apoptosis, and it has been considered one of the candidate genes for vitiligo because of its connections with human immune system. Overall, 3,120 study subjects with Chinese Han ancestry were recruited, and 15 pre-selected SNPs of GZMB were genotyped. Genetic association analyses were performed to evaluate the genetic risk of these SNPs to vitiligo. Further bioinformatic analyses were conducted to examine the potential biological function of targeted SNPs. The SNP rs8192917, a non-synonymous coding SNP, was identified to be significantly associated with the disease status of vitiligo, with OR = 1.39 and P = 1.92 × 10-8. Differences in the association signal can be observed in the stratification analyses of multiple clinical variables. Our positive results provide additional supportive evidence that GZMB gene is an important locus for vitiligo in Han Chinese population.

A common polymorphism of COMT was associated with symptomatic lumbar disc herniation based on a large sample with Chinese Han ancestry

Lumbar disc herniation (LDH) is a common spine disease characterized by a tear in the disc ring and bulges out at the soft portion. COMT is a protein coding gene located at 22q11.21, and its gene product is a major mammalian enzyme involved in the degradation of catecholamines. A total of 2,678 study subjects with Chinese Han ancestry were recruited and 15 SNPs were selected for genotyping in our study subjects. A synonymous coding SNP, rs4633, was identified to be significantly associated with the disease status of LDH after adjusting for BMI (OR = 0.76, P = 4.83 × 10⁻⁵). This SNP was also identified to be significantly associated with COMT gene expression in three types of human tissues. Minor alleles of rs4633 (T) increased the expression of COMT in these 3 tissues. We have identified a significant SNP of COMT, rs4633, which is associated with symptomatic LDH in a large Chinese Han-based sample of the study subjects. This significant finding is further replicated by haplotypic analysis. Evidence from bioinformatics analyses have shown that rs4633 is also significantly associated with the gene expression of COMT. Our findings provide additional supportive evidence for an important role of COMT gene in the symptomatic LDH susceptibility.

MDM4 contributes to the increased risk of glioma susceptibility in Han Chinese population

Recently, MDM4 gene has been reported to be a susceptibility gene for glioma in Europeans, but the molecular mechanism of glioma pathogenesis remains unknown. The aim of this study was to investigate whether common variants of MDM4 contribute to the risk of glioma in Han Chinese individuals. A total of 24 single-nucleotide polymorphisms (SNPs) of the MDM4 gene were assessed in a dataset of 562 glioma patients (non-glioblastoma) and 1,192 cancer-free controls. The SNP rs4252707 was found to be strongly associated with the risk of non-GBM (P = 0.000101, adjusted odds ratio (OR) = 1.34, 95% confidence interval (CI) = 1.16–1.55). Further analyses indicated that there was a significant association between A allele of rs4252707 associated with the increased non-GBM risk. Haplotype analysis also confirmed a result similar to that of the single-SNP analysis. Using stratification analyses, we found the association of rs4252707 with an increased non-GBM risk in adults (≥18 years, P = 0.0016) and individuals without IR exposure history (P = 0.0013). Our results provide strong evidence that the MDM4 gene is tightly linked to genetic susceptibility for non-GBM risk in Han Chinese population, indicating a important role for MDM4 gene in the etiology of glioma.

Common variants in the GNL3 contribute to the increasing risk of knee osteoarthritis in Han Chinese population

Osteoarthritis (OA) is a complex degenerative joint disorder, which is caused by both environmental and genetic factors. Previous studies have indicated that the GNL3 gene is associated with knee osteoarthritis (KOA) susceptibility in Europeans; however, the exact molecular mechanism is still unclear. In the present study, we investigated the potential genetic association of GNL3 with KOA in a two-stage sample of 6,704 individuals from the Han Chinese population. Subjects containing 1,052 KOA patients and 2,117 controls were considered the discovery dataset, while subjects consisting of 1,173 KOA patients and 2,362 controls were utilized as the replication dataset. Single-SNP association, imputation, and haplotypic association analyses were performed. The SNP of rs11177 in GNL3 was identified to be significantly associated with KOA after accounting for age, gender and BMI in both stages. The imputed SNP of rs6617 in SPCS1 was found to be strongly associated with KOA risk, and the significant association signal was confirmed in the replication stage. Moreover, a haplotype-based analysis also indicated a positive genetic effect of GNL3 on KOA susceptibility. In summary, our results proved that GNL3 plays an important role in the etiology of KOA, suggesting that GNL3 is a potential genetic modifier for KOA development.

Association of BET1L and TNRC6B with uterine leiomyoma risk and its relevant clinical features in Han Chinese population

Previous studies have shown that uterine leiomyomas (UL) are benign tumours with contributions from environmental and genetic factors. We aimed to replicate two initial significant genetic factors, TNRC6B and BET1L, in a Han Chinese population. A total of 2,055 study subjects were recruited, and 55 SNPs mapped to TNRC6B and BET1L were selected and genotyped in samples from these subjects. Genetic associations were analysed at both the single marker and haplotype levels. Associations between targeted SNPs and relevant clinical features of UL were analysed in case only samples. Functional consequences of significant SNPs were analysed by bioinformatics tools. Two SNPs, rs2280543 from BET1L (χ² = 18.3, OR = 0.64, P = 1.87 × 10⁻⁵) and rs12484776 from TNRC6B (χ² = 19.7, OR = 1.40, P = 8.91 × 10⁻⁶), were identified as significantly associated with the disease status of UL. Rs2280543 was significantly associated with the number of fibroid nodes (P = 0.0007), while rs12484776 was significantly associated with node size (χ² = 54.88, P = 3.44 × 10⁻¹¹). Both SNPs were a significant eQTL for their genes. In this study, we have shown that both BET1L and TNRC6B contributed to the risk of UL in Chinese women. Significant SNPs from BET1L and TNRC6B were also identified as significantly associated with the number of fibroid nodes and the size of the node, respectively.

Genetic polymorphisms of NOS2 and predisposition to fracture non-union: A case control study based on Han Chinese population

A non-union, especially atrophic non-unions, is a permanent failure of healing following a fracture and can be difficult to treat. Approximately 5–10% of fractures will result in a non-union during the healing process. non-unions can be classified into two types: atrophic non-union which is often due to impaired bone healing with a potential biological mechanism, and hypertrophic non-union which is due to inadequate fixation after fracture. Genetic variations also play an important role in the fracture healing response. Previous studies based on animal models have indicated that NOS2 might be greatly involved in the bone fracture healing process. In this case-control study, 346 nonunion patients were compared to 883 patients with normal fracture healing to investigate the potential genetic association between NOS2 and the fracture healing process using study subjects of Chinese Han ancestry. Twenty-seven single nucleotide polymorphisms (SNPs) covering NOS2 were genotyped in our study subjects and analyzed. In addition to the single marker-based analysis, we performed a gene-by-environment analysis to examine the potential interactions between genetic polymorphisms and some environmental factors. SNP rs2297514 showed significant association with the fracture healing process after adjusting for age and gender (OR = 1.38, P = 0.0005). Our results indicated that the T allele of rs2297514 significantly increased the risk of a non-union during the fracture healing process by 38% compared to the C allele. Further stratification analyses conducted for this SNP using data from subgroups classified by different sites of fracture indicated that significance could only be observed in the tibial diaphysis subgroup (N = 428, OR = 1.77, P = 0.0007) but not other groups including femur diaphysis, humeral shaft, ulnar shaft, and femur neck. Gene-by-environment interaction analyses of the three environmental factors showed no significant results. In this study, rs2297514 was significantly associated with the non-union status of fracture healing using a large Chinese population-based study sample. Our findings replicated those of a previous preliminary study and offered strong evidence linking NOS2 and fracture healing.

Common Variants in ALPL Gene Contribute to the Risk of Kidney Stones in the Han Chinese Population

OBJECTIVE

Kidney stone formation is a complex disorder that likely results from both dietary and genetic factors. A recent study identified an association between the risk of kidney stones and polymorphisms in the ALPL gene, but the study needs replication. To confirm whether the ALPL gene is universally associated with kidney stones, the present study further investigated polymorphisms of the ALPL gene in a Han Chinese population.

METHODS

A total of 331 kidney stone patients and 553 unrelated healthy controls were included in the present case-control study. We conducted genetic analyses to detect the association of 19 tagging single nucleotide polymorphisms (SNPs) with kidney stones. In addition, we examined the relations between targeted SNP(s) and several clinical characteristics of kidney stones in the patients.

RESULTS

Genetic association analyses using logistic regression models identified one ALPL SNP, rs1256328, which was significantly associated with the kidney stone disease status (OR = 1.52, p = 0.0009). No significant results were obtained through association tests between genotypes of this SNP and the various clinical characteristics of kidney stone patients.

CONCLUSION

The ALPL SNP, rs1256328, was identified as being significantly associated with kidney stone disease status in a large Chinese Han cohort. Our study replicated a previous genome-wide association study that was conducted in an Icelandic population.

Interaction of Cdk5 and cAMP/PKA Signaling in the Mediation of Neuropsychiatric and Neurodegenerative Diseases

Both cyclin-dependent kinase 5 (Cdk5) and cyclic AMP (cAMP)/protein kinase A (PKA) regulate fundamental central nervous system (CNS) functions including neuronal survival, neurite and axonal outgrowth, neuron development and cognition. Cdk5, a serine/threonine kinase, is activated by p35 or p39 and phosphorylates multiple signaling components of various pathways, including cAMP/PKA signaling. Here, we review the recent literature on the interaction between Cdk5 and cAMP/PKA signaling and their role in the mediation of CNS functions and neuropsychiatric and neurodegenerative diseases.

Depletion of D3 dopamine receptor affects methamphetamine-induced expression patterns of Pde4b and Atf3

The role of the D3 dopamine receptor (D3R) and the specific molecular mechanisms underlying the regulation of D3R via the cAMP signaling pathway in methamphetamine (METH) addiction are still unclear. Here, we measured changes in Pde4b and Atf3 in the cAMP signaling pathway of dopaminergic system components, including the nucleus accumbens (NAc), caudate putamen (CPu) and hippocampus (Hip), in D3R knockout mice(D3R-/-) 1h and 24h after METH-induced behavioral sensitization. We found that knocking out D3R attenuated METH-induced behavioral sensitization, and Pde4b and Atf3 exhibited different expression patterns in brain regions in response to METH. Knocking out D3R suppressed the METH-induced increase in Pde4b in the Hip of mice 24h after the final METH injection and augmented the METH-induced increase in Atf3 in the CPu of mice 1h after the final METH injection. Our study suggests that D3R knockout controls METH-induced behavioral sensitization via regulation of Pde4b and Atf3 in different brain regions. Furthermore, the responses of Pde4b and Atf3 to METH exposure depend on the specific region of the brain involved.

Genetic association study identified a 20 kb regulatory element in WLS associated with osteoporosis and bone mineral density in Han Chinese

Previous studies have linked the WNT pathway and human skeleton formation; therefore, genes related to WNT might contribute to the onset and development of osteoporosis. In this study, we investigated the potential genetic association of WLS, which encodes an important mediator in the WNT pathway, with osteoporosis and its related quantitative traits in a sample of 6,620 individuals from Han Chinese population. A two-stage approach, with a discovery stage with 859 cases and 1,690 controls and a validation stage with 1,039 cases and 3,032 controls, was applied in the study. Forty SNPs were genotyped in the discovery stage. The intronic SNP rs2566752 was identified to be significantly associated with osteoporosis (OR_discovery = 0.78, P_discovery = 3.73 × 10⁻⁵; OR_validation = 0.80, P_validation = 1.96 × 10⁻⁵). Two SNPs surrounding rs2566752 (in addition to this SNP itself) were identified to be associated with bone mineral density. In addition, we have identified a 20 kb peak region of H3K27Ac histone mark enrichment between rs2772304 and rs2566752. Our study suggested that WLS is an important locus for osteoporosis and its related quantitative phenotypes in Han Chinese population. Additional sequencing-based studies are needed to investigate the genetic architecture of this regulatory region and its relationship with osteoporosis-related phenotypes.

Evaluation of the association of UBASH3A and SYNGR1 with rheumatoid arthritis and disease activity and severity in Han Chinese

Rheumatoid arthritis (RA) is a common complex autoimmune disorder. UBASH3A and SYNGR1 were identified recently as susceptibility genes for RA risk in Korean and European populations, but the genetic aetiology and pathogenesis of RA have not been fully elucidated. We designed a two-stage case-control study including 916 RA patients and 2,266 unrelated healthy controls to identify common genetic variants in UBASH3A and SYNGR1 that predispose Han Chinese individuals to RA. We also evaluated the role of associated variants in clinical manifestations of RA, which may provide clues to the mechanisms involved in the aetiology of RA. We successfully identified two SNPs, rs1893592 in UBASH3A and rs909685 in SYNGR1, as significantly associated with the disease status of RA using our two-stage strategy. The rs1893592 SNP in UBASH3A was related with DAS28, CRP level and bone erosion. In summary, our results indicate that genetic variants in UBASH3A and SYNGR1 may modify individual susceptibility to RA in the Han Chinese population and support the role of the UBASH3A gene in RA disease activity and severity.

Evaluating the Association of Common Variants of the SLC44A4 Gene with Ulcerative Colitis Susceptibility in the Han Chinese Population

OBJECTIVE

The SLC44A4 gene was recently reported to be associated with ulcerative colitis (UC) susceptibility in the Indian and Japanese populations. The aim of our study was to investigate the association of common variants within the SLC44A4 gene and the susceptibility to UC among the Han Chinese.

METHODS

We examined 16 tag single nucleotide polymorphisms (SNPs) within the SLC44A4 gene in a Han Chinese population that consisted of 311 UC patients and 675 healthy controls; both SNP and haplotypic association analyses were performed.

RESULTS

We found that rs2736428 was significantly associated with UC risk (allelic p = 0.0004), and the CT and TT genotypes of rs2736428 had a higher distribution compared with the CC genotypes (genotypic p = 0.001), suggesting that the T allele was a risk allele (odds ratio = 1.45, 95% confidence interval = 1.18-1.78). Moreover, one haplotype block that included rs2736428 was found to be strongly associated with UC risk as well (global p < 0.001).

CONCLUSION

Our results provide further supportive evidence for an important role of the SLC44A4 gene in the pathogenesis of UC.

Association of common genetic variants in VEGFA with biliary atresia susceptibility in Northwestern Han Chinese

Biliary atresia (BA) is a major neonatal obliterative cholangiopathy, resulting in progressive cirrhosis. The gene VEGFA encodes a heparin-binding protein that is a regulator of angiogenesis and a mediator of inflammatory reactions, and accumulating evidence have indicated that VEGFA may play a possible role in the pathogenesis of BA. Our study aim was to evaluate the association of common variants within the VEGFA gene with BA susceptibility in Northwestern Han Chinese population. Forty tag SNPs within the VEGFA gene were selected in the study, and then subsequently genotyped in 1336 Northwestern Han Chinese individuals, consisting of 311 BA patients and 1025 healthy controls. The SNP rs3025039 was found to be strongly associated with BA risk (additive P=0.000264) in our sample, and the CC genotype of rs3025039 had higher prevalence than the other two genotypes, indicating the C allele is a risk allele with an odds ratio (OR) of 1.56 and 95% confidence interval (CI) of 1.23-1.99. Haplotype analyses showed that a LD block containing rs3025039 significantly correlated with BA risk (global P<0.001). Moreover, bioinformatics analysis indicated that hsa-mir-591 and VEGFA formed miRNA/SNP target duplexes if the rs3025039 allele was in the T form, suggesting that rs3025039 may alter VEGFA expression by affecting hsa-miR-591/single-nucleotide polymorphism target duplexes. Our results indicate additional evidence supporting that there is an important role of the VEGFA gene in the increased susceptibility of BA.

ABBREVIATIONS

Shaping mitochondrial dynamics: The role of cAMP signalling

In recent years, our idea of mitochondria evolved from "mere" energy and metabolite producers to key regulators of many cellular functions. In order to preserve and protect their functional status, these organelles engage a number of dynamic processes that allow them to decrease accumulated burden and maintain their homeostasis. Indeed, mitochondria can unite (fusion), divide (fission), position themselves strategically in the cell (motility/trafficking) and if irreversibly damaged or dysfunctional eliminated (mitophagy). These dynamic processes can be controlled both by mitochondrial and cellular signalling pathways, hence allowing mitochondria to tune their function to the cellular needs. Among the regulatory mechanisms, reversible phosphorylation downstream the cyclic AMP (cAMP) signalling cascade was shown to deeply influence mitochondrial dynamics. This review explores the emerging evidence suggesting that cAMP is a key player in the orchestration of mitochondrial fusion/fission, motility and mitophagy, extending the repertoire of this second messenger, which is now recognised as a major regulator of mitochondrial homeostasis.

Polymorphisms of RAD51B are associated with rheumatoid arthritis and erosion in rheumatoid arthritis patients

Rheumatoid arthritis (RA) is a common, chronic autoimmune disease affecting 0.5–1.0% of adults worldwide, including approximately 4.5–5.0 million patients in China. The genetic etiology and pathogenesis of RA have not yet been fully elucidated. Recently, one new RA susceptibility gene (RAD51B) has been identified in Korean and European populations. In this study, we designed a two-stage case-control study to further assess the relationship of common variants in the RAD51B gene with increased risk of RA in a total of 965 RA patients and 2,511 unrelated healthy controls of Han Chinese ancestry. We successfully identified a common variant, rs911263, as being significantly associated with the disease status of RA (P = 4.8 × 10⁻⁵, OR = 0.64). In addition, this SNP was shown to be related to erosion, a clinical assessment of disease severity in RA (P = 2.89 × 10⁻⁵, OR = 0.52). These findings shed light on the role of RAD51B in the onset and severity of RA. More research in the future is needed to clarify the underlying functional link between rs911263 and the disease.

Association of a common variant of SYNPO2 gene with increased risk of serous epithelial ovarian cancer

In China, the majority of ovarian cancer patients (80%–90%) are women who are diagnosed with epithelial ovarian cancer. The SYNPO2 gene has recently been reported to be associated with epithelial ovarian cancer in Europeans. To investigate the association of common variants of SYNPO2 gene with epithelial ovarian cancer in Han Chinese individuals, we designed a case–control study with 719 epithelial ovarian cancer patients and 1568 unrelated healthy controls of Han Chinese descent. A total of 49 tagging single-nucleotide polymorphisms were genotyped; single-single-nucleotide polymorphism association, imputation, and haplotypic association analyses were performed. The single-nucleotide polymorphism rs17329882 was found to be strongly associated with serous epithelial ovarian cancer and with ages ≤49 years, consistent with the pre-menopausal status of analyzed epithelial ovarian cancer cases. Odds ratios and 95% confidence intervals provided evidence of the risk effects of the C allele of the single-nucleotide polymorphism on epithelial ovarian cancer. Imputation analyses also confirmed the results with a similar pattern. Additionally, haplotype analyses indicated that the haplotype block that contained rs17329882 was significantly associated with epithelial ovarian cancer risk, specifically with the serous epithelial ovarian cancer subtype. In conclusion, our results show that SYNPO2 gene plays an important role in the etiology of epithelial ovarian cancer, suggesting that this gene may be a potential genetic modifier for developing epithelial ovarian cancer.

Additional Evidence Supports Association of Common Variants in COL11A1 with Increased Risk of Hip Osteoarthritis Susceptibility

OBJECTIVE

In a recent study single nucleotide polymorphisms (SNPs) in the COL11A1 gene were found to be associated with hip osteoarthritis (OA) among European populations. In this study, our aim was to identify common genetic variants in COL11A1 predisposing to primary hip OA in Han Chinese individuals.

METHODS

We designed a case-control study that included 313 hip OA patients and 911 unrelated healthy controls. Fourteen tagging single-nucleotide polymorphisms (SNPs) were genotyped, and single SNP and haplotypic association analyses were performed.

RESULTS

Two SNPs (rs1241164 and rs4907986) were found to be significantly associated with hip OA risk (adjusted p = 0.000731 and 0.000477). An increased risk of OA was associated with possession of the C allele of rs1241164 (adjusted odds ratio [OR] = 1.73, 95% confidence interval [CI] = 1.27-2.36) and the T allele of rs4907986 (adjusted OR = 1.72, 95% CI = 1.24-2.35). Similar results were confirmed via genotypic association analyses. Moreover, two different haplotype blocks, including rs1241164 and rs4907986, respectively, were found to be strongly associated with hip OA risk as well.

CONCLUSION

Variants in the COL11A1 gene modify individual susceptibility to hip OA in the Han Chinese population.

Association of common variants in MTAP with susceptibility and overall survival of osteosarcoma: a two-stage population-based study in Han Chinese

Osteosarcoma (OS) is a common malignant tumor, which exists widely in the bone of children and adolescents, and genetic factors may influence its susceptibility. Recently, the gene MTAP has been reported to be associated with OS in a Caucasian population. To investigate the association of common variants in MTAP with OS risk in Han Chinese individuals, we designed a two-stage case-control study with 392 OS patients and 1,578 unrelated healthy controls of Han Chinese individuals. A total of 17 tagging single nucleotide polymorphisms (SNPs) were firstly genotyped in the discovery stage, and single-SNP association and haplotypic association analyses have been performed. The SNP rs7023329 was found to be strongly associated with the OS risk (adjusted P = 0.002908), and the results of odds ratios (ORs) and 95% confidence intervals (CI) revealed increased risks from A allele of the SNP on OS (OR=1.33, 95% CI=1.13-1.62). The results were confirmed with a similar pattern in the validation stage (adjusted P = 0.006737, OR=1.49, 95% CI=1.11-2.00). Moreover, haplotypic analyses indicated that one haplotype block containing rs7023329 was significantly associated with OS risk in both stages (both global P<0.0001). The statistically significant association between the rs7023329 genotype and poor survival in OS patients was also observed. To sum up, our results prove that MTAP plays an important role in the etiology of OS, suggesting this gene as a potential genetic modifier for OS development.

Phosphodiesterase Inhibition and Regulation of Dopaminergic Frontal and Striatal Functioning: Clinical Implications

BACKGROUND

The fronto-striatal circuits are the common neurobiological basis for neuropsychiatric disorders, including schizophrenia, Parkinson's disease, Huntington's disease, attention deficit hyperactivity disorder, obsessive-compulsive disorder, and Tourette's syndrome. Fronto-striatal circuits consist of motor circuits, associative circuits, and limbic circuits. All circuits share 2 common features. First, all fronto-striatal circuits consist of hyper direct, direct, and indirect pathways. Second, all fronto-striatal circuits are modulated by dopamine. Intracellularly, the effect of dopamine is largely mediated through the cyclic adenosine monophosphate/protein kinase A signaling cascade with an additional role for the cyclic guanosine monophosphate/protein kinase G pathway, both of which can be regulated by phosphodiesterases. Phosphodiesterases are thus a potential target for pharmacological intervention in neuropsychiatric disorders related to dopaminergic regulation of fronto-striatal circuits.

METHODS

Clinical studies of the effects of different phosphodiesterase inhibitors on cognition, affect, and motor function in relation to the fronto-striatal circuits are reviewed.

RESULTS

Several selective phosphodiesterase inhibitors have positive effects on cognition, affect, and motor function in relation to the fronto-striatal circuits.

CONCLUSION

Increased understanding of the subcellular localization and unraveling of the signalosome concept of phosphodiesterases including its function and dysfunction in the fronto-striatal circuits will contribute to the design of new specific inhibitors and enhance the potential of phosphodiesterase inhibitors as therapeutics in fronto-striatal circuits.