OBJECTIVE: Circular RNAs (circRNAs) participate in several important pathological processes and have been used in the diagnosis and treatment of various diseases. This study aimed to investigate the role of circRNAs in neural tube defects (NTDs). METHOD: We characterized circRNA-associated competitive endogenous RNA (ceRNA) networks in brain tissue of low folate -induced NTDs mouse at embryonic day 13.5 by high-throughput sequencing. The expression levels of Circzfp644, miR-20-5p and Gas7 were detected by RT-PCR. Gas7 and Circzfp644 functions were determined by miRNA-mimics and inhibitors in mouse teratocarcinoma cells (F9 cells), and luciferase gene reporter assay was assessed in the F9 cells. In addition, the expression levels of Circzfp644, miR-20-5p and Gas7 were determined by Nanostring in human NTDs tissues. RESULTS: We detected 57 circRNA transcripts, 16 miRNAs, and 148 mRNAs that were significantly dysregulated in NTDs brain tissues compared with their expression levels in control (normal) tissues. Circzfp644 shared miRNA response elements with the growth arrest specific 7 ( Gas7) gene and competitively bound with miR-20-5p to increase the expression of Gas7. Downregulation of Circzfp644 and Gas7 and upregulation of miR-20-5p were found in human NTD tissue. CONCLUSION This study provides new perspectives on the role of circRNAs in nervous system development and the pathogenesis of NTDs.
Humans ; Animals ; Mice ; RNA, Circular/genetics* ; MicroRNAs/metabolism* ; Down-Regulation ; Neural Tube Defects/genetics* ; Folic Acid

OBJECTIVE: To explore the characteristics of differentially methylated genes and gene ontology associated with neural tube defects (NTDs). METHODS: Twelve subjects from 3 NTDs pedigrees were enrolled. Patients with NTDs have served as the case group, while their family members with normal phenotypes have served as the control group. Genomic DNA was extracted from peripheral venous blood samples of the families and used for DNA methylation analysis. Pairwise comparison was carried out primarily for patient-offspring pairs, and co-segregation of methylation pattern with NTDs was analyzed. Pathway related to differentially methylated genes was predicted with DAVID software. RESULTS: Pairwise comparison indicated that VTRNA2-1 was the only gene in which all CpG sites were methylated. Co-segregation of VTRNA2-1 gene methylation with NTDs was found in all pedigrees. Pathways of hypermethylated genes included plasma membrane component, regulation of cellular protein metabolic process, and regulation of actin cytoskeleton organization, while the pathways of hypomethylated genes have included transcription regulator activity, cell adhesion, and neuronal differentiation. CONCLUSION Methylation of the VTRNA2-1 gene has co-segregated with NTDs in the studied pedigrees. The pathways of differentially methylated genes has involved with mechanism of neural tube development.
CpG Islands ; DNA Methylation ; Gene Ontology ; Humans ; MicroRNAs ; genetics ; Neural Tube Defects ; genetics ; Pedigree

Folic Acid ; metabolism ; Homocysteine ; metabolism ; Humans ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Neural Tube Defects ; genetics ; metabolism ; Polymorphism, Genetic

OBJECTIVETo clone down-regulated genes in neural tube defects of golden hamster induced by hyperthermia and to explore the molecular mechanism.

METHODSA reversed subtractive cDNA library was constructed using suppression subtractive hybridization. Clones with inserts were selected by combination of alpha complementary phenomenon and colony PCR. Then sequence and homology analysis of the inserts were made. And mRNA expression conditions were confirmed by Northern blot.

RESULTSThe reversed subtractive cDNA library was successfully constructed. Fifteen recombinant clones were sequenced and recognized homologous to known genes. The results of Northern blot showed that all these genes were down-regulated in defected neural tubes induced by hyperthermia compared to normal developed neural tubes.

CONCLUSIONSome important genes are identified which might be involved in neural tube defects induced by hyperthermia.

Animals ; Blotting, Northern ; Cloning, Molecular ; Cricetinae ; Female ; Gene Library ; Hyperthermia, Induced ; adverse effects ; Mesocricetus ; Neural Tube Defects ; etiology ; genetics

BACKGROUNDThe 5,10-methylenetetrahydrofolate reductase (MTHFR) and methionine synthase (MS) are attractive candidates for screening for risk of neural tube defects (NTDs). The aim of the current study was to investigate maternal MTHFR and MS polymorphisms and the interaction between them and their influence on children with NTDs in the Shanxi Province of northern China.

METHODSFifty-one mothers who previously had children with NTDs constituted the case group and 51 age-matched mothers with children that were unaffected by any birth defects constituted the control group. All subjects were genotyped for MTHFR C677T and MS A2756G polymorphisms. SPSS 11.5 software package was used for all analyses.

RESULTSThere was a significant difference for MTHFR genotype distribution for one site (C677T) between the case and control groups. The T allele frequencies were significantly higher in the case group than in the control group (55.9% vs. 35.3%, P < 0.05). A lack of association was observed for the MS A2756G polymorphism. There was an interaction between the maternal MTHFR C677T genotype and MS A2756G genotype.

CONCLUSIONGenetic interaction between MTHFR and MS genes raises the probability of neural tube defects.

5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase ; genetics ; China ; Female ; Gene Frequency ; genetics ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Neural Tube Defects ; epidemiology ; genetics ; Polymorphism, Genetic ; genetics

BACKGROUNDNeural tube defects are the most common human birth defects. The causes are multifactorial with complex genetic and environmental factors, although the exact genetic causes are unknown. This research was conducted to study the frequency of Msx2 gene polymorphisms in 59 women with a history of pregnancy with a neural tube defect and in 73 healthy controls. We aimed to determine the effect of this genetic polymorphism on the incidence of neural tube defects in the Han Chinese population.

METHODSWe studied 59 mothers with at least one previous child with a neural tube defect (the case group) and 73 case-control subjects during the same period, from Shanxi Province, China. We analyzed the genotypic distributions and allele frequencies of Msx2 C386T polymorphisms in DNA samples from the case and control groups. A three-dimensional protein model was predicted using Swiss-Pdb Viewer software version 4.0. Disease association was analyzed using chi-square tests.

RESULTSSignificant differences were observed in the genotypes and allele frequencies of the Msx2 C386T allele between the case and control groups (CT: 32% vs. 15%, P = 0.0073 and TT 15% vs. 4%, P = 0.013, respectively). Logistic regression analysis showed that the C386T mutation is a potential risk factor for neural tube defects (P < 0.05; OR: 3.466; 95%CI: 1.831 - 6.560). Three-dimensional structure prediction revealed that the Msx2 C386T mutation results in a threonine substitution for methionine at position 129 of exon 2, which might lead to structural mutations or dysfunctions in the protein encoded by Msx2.

CONCLUSIONMaternal Msx2 C386T gene polymorphisms were associated with fetal neural tube defects in Han Chinese women in Shanxi Province.

Adult ; Asian Continental Ancestry Group ; genetics ; China ; Female ; Homeodomain Proteins ; chemistry ; genetics ; metabolism ; Humans ; Neural Tube Defects ; epidemiology ; genetics ; Polymerase Chain Reaction ; Polymorphism, Single Nucleotide ; genetics ; Pregnancy ; Protein Structure, Secondary ; Young Adult

OBJECTIVETo explore the risk factors of neural tube defects (NTDs) in Shanxi province where the incidence of NTDs had been the highest in China.

METHODS1:1 matched case-control study was used. All the objects collected from hospitals were investigated in standardized questionnaires about susceptible risk factors for NTDs and were genotyped for methylenetetrahydrofolate reductase (MTHFR) C667T polymorphism by PCR-RFLP method. The risk factors of NTDs were analyzed by conditional logistic regression and by SPSS 11.5 statistical software. We also analyzed the univariable and multi-variables in order to independently investigate the MTHFR genotype and maternal periconceptional adverse factors influencing on NTDs.

RESULTSComparing MTHFR gene frequency between case group and control group, our results showed that three genotypes were found in MTHFR C677T. There was significant difference between two groups at 0.01 level (chi2 = 14.61, P = 0.001) about the three genotypes. The MTHFR T allele frequency of mother with NTDs (60.6%) was higher than that of the control (41.4%), and there was significant difference between them (chi2 = 14.59, P < 0.001). By univariate conditional logistic regression analysis, it was indicated that 15 factors were correlated with NTDs (P < 0.05) in the level alpha = 0.05. By multi-variables conditional logistic regression analysis, four factors were connected to NTDs: frequency of pregnancy (OR = 2.87, 95%CI: 1.28 - 6.44), contacting chemical combination in early pregnancy (OR = 16.18, 95%CI: 1.18 - 221.59), frequent taking of germinated potato (OR = 4.66, 95%CI: 1.78 - 12.17) and MTHFR C677T mutation (OR = 2.13, 95%CI: 1.08 - 4.21).

CONCLUSIONFactors as 'frequency of pregnancy', 'history of contacting chemicals', 'taking germinated potatoes in early pregnancy', as well as 'MTHFR C677T mutation' in mothers were important risk factors affecting the occurrence of NTDs in Shanxi province.

Adult ; Case-Control Studies ; China ; epidemiology ; Female ; Gene Frequency ; Genotype ; Humans ; Logistic Models ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Mutation ; Neural Tube Defects ; epidemiology ; genetics ; Parity ; Polymorphism, Genetic ; Pregnancy ; Risk Factors ; Surveys and Questionnaires

OBJECTIVETo study the association between reduced folate carrier gene (RFC1 A80G) polymorphism and the risk for child with neural tube defects (NTDs), and to provide epidemiological evidence for the existence of NTDs genetic marker.

METHODSRFC1 (A80G) genotypes were detected using RFLP-PCR for blood DNA of 104 families with NTDs-affected children and 100 control families with no history of child-affected birth defects. Case-control study and transmission/disequilibrium test(TDT) for the RFC1 genotype of NTDs pedigree were carried out.

RESULTSThe G allele frequency of children with NTDs was higher than that of controls when compared to A allele( OR = 1. 64, 95% CI :1.08-2.49). The offspring of the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to the AA genotype (OR = 2.56, 95% CI: 1.04-6.36) in our study population. There was evidence of association between G allele and the risk of parent having a child with NTDs (OR = 1.56, 95% CI: 1.07-2.28) in the TDT analysis.

CONCLUSIONOur findings indicated that there was potential association between offspring RFC1 GG genotype and the risk of NTDs, and the G allele was a possible susceptible gene marker for an increased NTDs risk in the Chinese population.

Case-Control Studies ; Child ; Child, Preschool ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Infant ; Male ; Membrane Transport Proteins ; genetics ; Neural Tube Defects ; genetics ; Parents ; Polymorphism, Genetic ; Reduced Folate Carrier Protein

OBJECTIVETo describe the distribution of reduced folate carrier gene (RFC1)genotype and allele frequency between southern and northern, female and male Chinese population.

METHODRFC1 (A80G) genotype was detected, using polymerase chain reaction-restriction fragment length polymorphism (RFLP-PCR) on 720 blood spot DNA from the normal subjects.

RESULTSThe frequencies of the northern population with AA, GG and GA genotypes were 22.28%, 31.09% and 46.63%, and the frequencies of the southern population were 18.56%, 22.75% and 58.68%, respectively. Findings showed that there were significant differences between southerners and northerners in RFC1 (A80G) genotype (P < 0.01). There was no significant difference between G allele frequency of the northern (52.10%) and southern population (54.40%). The frequencies of male with RFC1 (A80G) AA, GG and GA genotype were 24.88%, 25.85% and 49.27%, and among female were 18.83%, 27.77% and 53.40%, respectively. There were no significant differences between male and female in RFC1 genotype (P > 0.05), or between G allele frequency in female (50.49%) and that in male (54.47%).

CONCLUSIONSThe distribution of RFC1 genotype seemed to be consistent with neural tube defects (NTDs) while its prevalence among the northerners was higher than that of southerners, with female having a higher NTDs prevalence. This study provided genetic epidemiological data for etiological hypothesis between RFC1 and diseases relative to folate metabolism.

Alleles ; Carrier Proteins ; genetics ; physiology ; China ; ethnology ; Female ; Folic Acid ; metabolism ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; Membrane Proteins ; genetics ; Membrane Transport Proteins ; Methylenetetrahydrofolate Reductase (NADPH2) ; Mutation ; genetics ; Neural Tube Defects ; genetics ; Polymerase Chain Reaction ; Polymorphism, Genetic ; genetics ; Polymorphism, Restriction Fragment Length

OBJECTIVETo search the interaction between reduced folate carrier gene (RFC1 A80G) polymorphism of children with neural tube defects (NTDs) and maternal periconceptional no supplementation of folic acid. The purpose is to provide the epidemiological evidence for finding genetic marker of NTDs.

METHODSRFC1 (A80G) genotype was detected using PCR-restricted fragment length polymorphism for the blood DNA of 104 trios with NTDs-affected child, and 100 control families with non-malformed control children. The authors investigated the gene-environment interactions between the offspring RFC1 genotype and maternal periconceptional folic acid supplementation through a case-control study.

RESULTSIt was observed that the offspring with the GG genotype were associated with a 2.56-fold increased risk of NTDs when compared to those with the AA genotype (OR = 2.56; 95% CI = 1.04-6.36) in this population under investigation. The risk of mothers who did not take folic acid for having an NTDs-affected infants was 7.69 (95% CI = 2.86-21.75). Among the mothers who did not utilize folic acid supplements, the NTDs risk was 3.30 (95% CI = 1.15-9.65) for offspring with the GG genotype, compared to the reference (AA) genotype. Children who had the GG genotype and whose mothers did not take folic acid had an elevated risk for NTDs (OR = 8.80, 95% CI = 2.86 - 29.82), compared to "offspring with AA or GA genotype" and "maternal folic acid use", the interactive coefficient being 1.45.

CONCLUSIONThe above findings indicate that the RFC1 genotype (GG) is a possible susceptible gene marker for an increased NTDs risk in Chinese population, and there is a potential gene-nutrient interaction between offspring RFC1 GG genotype and maternal periconceptional intake of folic acid on the risk of NTDs. However,the sample size of this study was limited, a larger sample of population-based study is required to pursue the initial observation.

Adult ; Case-Control Studies ; Child ; Child, Preschool ; Dietary Supplements ; Female ; Folic Acid ; administration & dosage ; Genetic Predisposition to Disease ; genetics ; Genotype ; Humans ; Male ; Membrane Transport Proteins ; genetics ; Neural Tube Defects ; genetics ; prevention & control ; Polymorphism, Genetic ; genetics ; Reduced Folate Carrier Protein ; Vitamin B Complex ; administration & dosage