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Parental Decision-Making and Acceptance of Newborn Bloodspot Screening: An Exploratory Study  [PDF]
Stuart G. Nicholls, Kevin W. Southern
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0079441
Abstract: Objective Newborn bloodspot screening is an internationally established public health measure. Despite this, there is a paucity of information relating to the decision-making process that parents go through when accepting newborn screening. This is important as screening panels are expanding; potentially leading to an increasing amount of complex information. This study sought to understand the factors that influence parental decisions and roles they play in the decision-making process. Patients and Methods Qualitative thematic evaluation of semi structured interviews with parents whose children had recently undergone newborn screening in the Merseyside and Cheshire region of England, UK. Results Eighteen interviews with first time parents (n = 12) and those with previous children (n = 6). Seven factors were identified as being either explicitly or implicitly related to parental decision-making: Experience, Attitudes to medicine, Information-seeking behaviour, Perceived knowledge, Attitudes to screening, and Perceived choice, all of which ultimately impact on Perceived decisional quality. Conclusions These results indicate that while content is important, other contextual factors such as personal experience, perceived choice, and general attitudes toward medicine, are also highly influential. In particular, relationships with key healthcare professionals are central to information collection, attitudes toward screening, and the level of deliberation that is invested in decisions to accept newborn bloodspot screening.
Impact of parental ages and other characteristics at childbearing on congenital anomalies: Results for the Czech Republic, 2000-2007  [cached]
Jitka Rychtarikova,Catherine Gourbin,Guillaume Wunsch,Antonín ?ípek
Demographic Research , 2013,
Abstract: BACKGROUND If the impact of maternal age at childbearing on congenital anomalies is well-known for the occurrence of Down syndrome, less is known concerning its effects on other major anomalies. Information is even scarcer for the possible effects of other maternal characteristics and of age of the father. OBJECTIVE We present new results on the associations between parental ages and other maternal characteristics, on the one hand, and congenital anomalies, on the other hand, using data linkage between three Czech registries on mother, newborn, and malformations, for the period 2000-2007. METHODS As the variables are in categorical format, binary logistic regression is used in order to investigate the relationship between presence/absence of a congenital anomaly, for each of the eleven types of anomalies considered, and the set of predictors. RESULTS This research confirms the impact of a higher age of the mother on Down syndrome and on other chromosomal anomalies. Paternal age is not associated with chromosomal anomalies and, in this Czech population, has a rather slight effect on some of the congenital anomalies examined. Another finding of the present study is the possible role of various other maternal characteristics on congenital malformations. CONCLUSIONS Based on a large data set, this study concludes that both parental ages can be associated with congenital anomalies of the child, and that maternal characteristics other than age have also to be considered. COMMENTS Risk factors can be tentatively proposed if they are based on a plausible and suitably tested explanatory mechanism. Unfortunately, in the majority of individual cases of congenital anomaly, the cause of the condition is still unknown and suspected to be an interaction of multiple environmental and genetic factors.
Parental and Grandparental Ages in the Autistic Spectrum Disorders: A Birth Cohort Study  [PDF]
Jean Golding,Colin Steer,Marcus Pembrey
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0009939
Abstract: A number of studies have assessed ages of parents of children with autistic spectrum disorders (ASD), and reported both maternal and paternal age effects. Here we assess relationships with grandparental ages.
Placental 11-Beta Hydroxysteroid Dehydrogenase Methylation Is Associated with Newborn Growth and a Measure of Neurobehavioral Outcome  [PDF]
Carmen J. Marsit, Matthew A. Maccani, James F. Padbury, Barry M. Lester
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0033794
Abstract: Background There is growing evidence that the intrauterine environment can impact the neurodevelopment of the fetus through alterations in the functional epigenome of the placenta. In the placenta, the HSD11B2 gene encoding the 11-beta hydroxysteroid dehydrogenase enzyme, which is responsible for the inactivation of maternal cortisol, is regulated by DNA methylation, and has been shown to be susceptible to stressors from the maternal environment. Methodology/Principal Findings We examined the association between DNA methylation of the HSD11B2 promoter region in the placenta of 185 healthy newborn infants and infant and maternal characteristics, as well as the association between this epigenetic variability and newborn neurobehavioral outcome assessed with the NICU Network Neurobehavioral Scales. Controlling for confounders, HSD11B2 methylation extent is greatest in infants with the lowest birthweights (P = 0.04), and this increasing methylation was associated with reduced scores of quality of movement (P = 0.04). Conclusions/Significance These results suggest that factors in the intrauterine environment which contribute to birth outcome may be associated with placental methylation of the HSD11B2 gene and that this epigenetic alteration is in turn associated with a prospectively predictive early neurobehavioral outcome, suggesting in some part a mechanism for the developmental origins of infant neurological health.
The Global DNA Methylation Surrogate LINE-1 Methylation Is Correlated with MGMT Promoter Methylation and Is a Better Prognostic Factor for Glioma  [PDF]
Fumiharu Ohka,Atsushi Natsume,Kazuya Motomura,Yugo Kishida,Yutaka Kondo,Tatsuya Abe,Yoko Nakasu,Hiroki Namba,Kenji Wakai,Takashi Fukui,Hiroyuki Momota,Kenichiro Iwami,Sayano Kinjo,Maki Ito,Masazumi Fujii,Toshihiko Wakabayashi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0023332
Abstract: Gliomas are the most frequently occurring primary brain tumor in the central nervous system of adults. Glioblastoma multiformes (GBMs, WHO grade 4) have a dismal prognosis despite the use of the alkylating agent, temozolomide (TMZ), and even low grade gliomas (LGGs, WHO grade 2) eventually transform to malignant secondary GBMs. Although GBM patients benefit from promoter hypermethylation of the O6-methylguanine-DNA methyltransferase (MGMT) that is the main determinant of resistance to TMZ, recent studies suggested that MGMT promoter methylation is of prognostic as well as predictive significance for the efficacy of TMZ. Glioma-CpG island methylator phenotype (G-CIMP) in the global genome was shown to be a significant predictor of improved survival in patients with GBM. Collectively, we hypothesized that MGMT promoter methylation might reflect global DNA methylation. Additionally in LGGs, the significance of MGMT promoter methylation is still undetermined. In the current study, we aimed to determine the correlation between clinical, genetic, and epigenetic profiles including LINE-1 and different cancer-related genes and the clinical outcome in newly diagnosed 57 LGG and 54 GBM patients. Here, we demonstrated that (1) IDH1/2 mutation is closely correlated with MGMT promoter methylation and 1p/19q codeletion in LGGs, (2) LINE-1 methylation levels in primary and secondary GBMs are lower than those in LGGs and normal brain tissues, (3) LINE-1 methylation is proportional to MGMT promoter methylation in gliomas, and (4) higher LINE-1 methylation is a favorable prognostic factor in primary GBMs, even compared to MGMT promoter methylation. As a global DNA methylation marker, LINE-1 may be a promising marker in gliomas.
Influence of Prenatal Arsenic Exposure and Newborn Sex on Global Methylation of Cord Blood DNA  [PDF]
J. Richard Pilsner, Megan N. Hall, Xinhua Liu, Vesna Ilievski, Vesna Slavkovich, Diane Levy, Pam Factor-Litvak, Mahammad Yunus, Mahfuzar Rahman, Joseph H. Graziano, Mary V. Gamble
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0037147
Abstract: Background An emerging body of evidence indicates that early-life arsenic (As) exposure may influence the trajectory of health outcomes later in life. However, the mechanisms underlying these observations are unknown. Objective The objective of this study was to investigate the influence of prenatal As exposure on global methylation of cord blood DNA in a study of mother/newborn pairs in Matlab, Bangladesh. Design Maternal and cord blood DNA were available from a convenience sample of 101 mother/newborn pairs. Measures of As exposure included maternal urinary As (uAs), maternal blood As (mbAs) and cord blood As (cbAs). Several measures of global DNA methylation were assessed, including the [3H]-methyl-incorporation assay and three Pyrosequencing assays: Alu, LINE-1 and LUMA. Results In the total sample, increasing quartiles of maternal uAs were associated with an increase in covariate-adjusted means of newborn global DNA methylation as measured by the [3H]-methyl-incorporation assay (quartile 1 (Q1) and Q2 vs. Q4; p = 0.06 and 0.04, respectively). Sex-specific linear regression analyses, while not reaching significance level of 0.05, indicated that the associations between As exposures and Alu, LINE-1 and LUMA were positive among male newborns (N = 58) but negative among female newborns (N = 43); tests for sex differences were borderline significant for the association of cbAs and mbAs with Alu (p = 0.05 and 0.09, respectively) and for the association between maternal uAs and LINE-1 (p = 0.07). Sex-specific correlations between maternal urinary creatinine and newborn methyl-incorporation, Alu and LINE-1 were also evident (p<0.05). Conclusions These results suggest that prenatal As exposure is associated with global DNA methylation in cord blood DNA, possibly in a sex-specific manner. Arsenic-induced epigenetic modifications in utero may potentially influence disease outcomes later in life. Additional studies are needed to confirm these findings and to examine the persistence of DNA methylation marks over time.
Non-imprinted allele-specific DNA methylation on human autosomes
Yingying Zhang, Christian Rohde, Richard Reinhardt, Claudia Voelcker-Rehage, Albert Jeltsch
Genome Biology , 2009, DOI: 10.1186/gb-2009-10-12-r138
Abstract: We studied DNA methylation of cytosine-guanine dinucleotide (CpG) islands on chromosome 21 in leukocytes from several healthy individuals and observed novel cases of pronounced differential methylation of alleles. Allele-specific methylation affected complete CpG islands with methylation differences between alleles of up to 85%. The methylation differences between alleles were strongly correlated with the genotypes, excluding a connection to imprinting. We show that allele-specific methylation can lead to allelic repression of the methylated gene copy. Based on our results, allele-specific methylation is likely to affect about 10% of all human genes and to contribute to allele-specific expression and monoallelic gene silencing. Therefore, allele-specific methylation represents an epigenetic pathway of how genetic polymorphisms may lead to phenotypic variability. In most cases, we observed that some, but not all, heterozygous individuals showed allele-specific methylation, suggesting that allele-specific methylation is the outcome of an epigenetic drift, the direction of which is determined by the genetic differences between the alleles. We could show that the tendency to acquire hypermethylation in one allele was inherited.We observed that larger differences in methylation levels between individuals were often coupled to allele-specific methylation and genetic polymorphisms, suggesting that the inter-individual variability of DNA methylation is strongly influenced by genetic differences. Therefore, genetic differences must be taken into account in future comparative DNA methylation studies.DNA methylation is a major epigenetic process that plays essential roles in gene expression regulation, development and disease [1-3]. In mammals, differential DNA methylation between alleles occurs in imprinted genes [4,5] and on the female X chromosomes [6,7]. So far, there have been few reports about allele-specific methylation (ASM) on autosomes not connected to the parental i
Natural variation in DNA methylation in ribosomal RNA genes of Arabidopsis thaliana
Hye Woo, Eric J Richards
BMC Plant Biology , 2008, DOI: 10.1186/1471-2229-8-92
Abstract: Here, we explored the extent of naturally-occurring variation in NOR DNA methylation among accessions of the flowering plant Arabidopsis thaliana. DNA methylation in coding regions of rRNA genes was positively correlated with copy number of 45S rRNA gene and DNA methylation in the intergenic spacer regions. We investigated the inheritance of NOR DNA methylation patterns in natural accessions with hypomethylated NORs in inter-strain crosses and defined three different categories of inheritance in F1 hybrids. In addition, subsequent analysis of F2 segregation for NOR DNA methylation patterns uncovered different patterns of inheritance. We also revealed that NOR DNA methylation in the Arabidopsis accession Bor-4 is influenced by the vim1-1 (variant in methylation 1-1) mutation, but the primary effect is specified by the NORs themselves.Our results indicate that the NORs themselves are the most significant determinants of natural variation in NOR DNA methylation. However, the inheritance of NOR DNA methylation suggests the operation of a diverse set of mechanisms, including inheritance of parental methylation patterns, reconfiguration of parental NOR DNA methylation, and the involvement of trans-acting modifiers.DNA methylation is an important mechanism for establishing stable heritable epigenetic marks that modify the information content of the underlying genetic sequence [1]. In plants and vertebrates, DNA methylation is important for gene regulation, genomic imprinting, heterochromatin assembly, and protection of the genome against migrating transposable elements [2,3]. Both forward and reverse genetic approaches have identified important components of DNA methylation systems in eukaryotes, including cytosine-DNA-methyltransferases (DNMTs) and chromatin modification enzymes [2,4,5]. In addition to conventional genetic approaches, research based on the analysis of natural genetic variation has increased dramatically in recent years [6-9]. In the flowering plant, Arabi
Effects of arsenic exposure on DNA methylation in cord blood samples from newborn babies and in a human lymphoblast cell line
Ponpat Intarasunanont, Panida Navasumrit, Somchamai Waraprasit, Krittinee Chaisatra, William A Suk, Chulabhorn Mahidol, Mathuros Ruchirawat
Environmental Health , 2012, DOI: 10.1186/1476-069x-11-31
Abstract: For the exposure in utero study, a total of seventy-one newborns (fifty-five arsenic-exposed and sixteen unexposed newborns) were recruited. Arsenic concentrations in the drinking water were measured, and exposure in newborns was assessed by measurement of arsenic concentrations in cord blood, nails and hair by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). In the in vitro study, human lymphoblasts were treated with arsenite at 0-100 μM for two, four and eight hours (short-term) and at 0, 0.5 and 1.0 μM for eight-weeks period (long-term). DNA methylation was analyzed in cord blood lymphocytes and lymphoblasts treated with arsenite in vitro. Global DNA methylation was determined as LINE-1 methylation using combined bisulfite restriction analysis (COBRA) and total 5-methyldeoxycytidine (5MedC) content which was determined by HPLC-MS/MS. Methylation of p53 was determined at the promoter region using methylation-specific restriction endonuclease digestion with MspI and HpaII.Results showed that arsenic-exposed newborns had significantly higher levels of arsenic in cord blood, fingernails, toenails and hair than those of the unexposed subjects and a slight increase in promoter methylation of p53 in cord blood lymphocytes which significantly correlated with arsenic accumulation in nails (p < 0.05) was observed, while LINE-1 methylation was unchanged. Short-term in vitro arsenite treatment in lymphoblastoid cells clearly demonstrated a significant global hypomethylation, determined as reduction in LINE-1 methylation and total 5-MedC content, and p53 hypermethylation (p < 0.05). However, a slight LINE-1 hypomethylation and transient p53 promoter hypermethylation were observed following long-term in vitro treatment.This study provides an important finding that in utero arsenic exposure affects DNA methylation, particularly at the p53 promoter region, which may be linked to the mechanism of arsenic carcinogenesis and the observed increased incidence of cancer later in
Genome-Wide Methylation and Gene Expression Changes in Newborn Rats following Maternal Protein Restriction and Reversal by Folic Acid  [PDF]
Gioia Altobelli, Irina G. Bogdarina, Elia Stupka, Adrian J. L. Clark, Simon Langley-Evans
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0082989
Abstract: A large body of evidence from human and animal studies demonstrates that the maternal diet during pregnancy can programme physiological and metabolic functions in the developing fetus, effectively determining susceptibility to later disease. The mechanistic basis of such programming is unclear but may involve resetting of epigenetic marks and fetal gene expression. The aim of this study was to evaluate genome-wide DNA methylation and gene expression in the livers of newborn rats exposed to maternal protein restriction. On day one postnatally, there were 618 differentially expressed genes and 1183 differentially methylated regions (FDR 5%). The functional analysis of differentially expressed genes indicated a significant effect on DNA repair/cycle/maintenance functions and of lipid, amino acid metabolism and circadian functions. Enrichment for known biological functions was found to be associated with differentially methylated regions. Moreover, these epigenetically altered regions overlapped genetic loci associated with metabolic and cardiovascular diseases. Both expression changes and DNA methylation changes were largely reversed by supplementing the protein restricted diet with folic acid. Although the epigenetic and gene expression signatures appeared to underpin largely different biological processes, the gene expression profile of DNA methyl transferases was altered, providing a potential link between the two molecular signatures. The data showed that maternal protein restriction is associated with widespread differential gene expression and DNA methylation across the genome, and that folic acid is able to reset both molecular signatures.
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