1
|
Martinez ME, Karaczyn A, Wu Z, Bennett CA, Matoin KL, Daigle HM, Hernandez A. Transgenerational epigenetic self-memory of Dio3 dosage is associated with Meg3 methylation and altered growth trajectories and neonatal hormones. Epigenetics 2024; 19:2376948. [PMID: 38991122 PMCID: PMC11244338 DOI: 10.1080/15592294.2024.2376948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 07/02/2024] [Indexed: 07/13/2024] Open
Abstract
Intergenerational and transgenerational epigenetic effects resulting from conditions in previous generations can contribute to environmental adaptation as well as disease susceptibility. Previous studies in rodent and human models have shown that abnormal developmental exposure to thyroid hormone affects endocrine function and thyroid hormone sensitivity in later generations. Since the imprinted type 3 deiodinase gene (Dio3) regulates sensitivity to thyroid hormones, we hypothesize its epigenetic regulation is altered in descendants of thyroid hormone overexposed individuals. Using DIO3-deficient mice as a model of developmental thyrotoxicosis, we investigated Dio3 total and allelic expression and growth and endocrine phenotypes in descendants. We observed that male and female developmental overexposure to thyroid hormone altered total and allelic Dio3 expression in genetically intact descendants in a tissue-specific manner. This was associated with abnormal growth and neonatal levels of thyroid hormone and leptin. Descendant mice also exhibited molecular abnormalities in the Dlk1-Dio3 imprinted domain, including increased methylation in Meg3 and altered foetal brain expression of other genes of the Dlk1-Dio3 imprinted domain. These molecular abnormalities were also observed in the tissues and germ line of DIO3-deficient ancestors originally overexposed to thyroid hormone in utero. Our results provide a novel paradigm of epigenetic self-memory by which Dio3 gene dosage in a given individual, and its dependent developmental exposure to thyroid hormone, influences its own expression in future generations. This mechanism of epigenetic self-correction of Dio3 expression in each generation may be instrumental in descendants for their adaptive programming of developmental growth and adult endocrine function.
Collapse
Affiliation(s)
- M. Elena Martinez
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Aldona Karaczyn
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Zhaofei Wu
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Christian A. Bennett
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Kassey L. Matoin
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Heather M. Daigle
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
| | - Arturo Hernandez
- Center for Molecular Medicine, MaineHealth Institute for Research, MaineHealth, Scarborough, ME, USA
- Graduate School for Biomedical Sciences and Engineering, University of Maine, Orono, ME, USA
- Department of Medicine, Tufts University School of Medicine, Boston, MA, USA
| |
Collapse
|
2
|
Abedini SS, Akhavantabasi S, Liang Y, Heng JIT, Alizadehsani R, Dehzangi I, Bauer DC, Alinejad-Rokny H. A critical review of the impact of candidate copy number variants on autism spectrum disorder. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2024; 794:108509. [PMID: 38977176 DOI: 10.1016/j.mrrev.2024.108509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 04/14/2024] [Accepted: 07/02/2024] [Indexed: 07/10/2024]
Abstract
Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder (NDD) influenced by genetic, epigenetic, and environmental factors. Recent advancements in genomic analysis have shed light on numerous genes associated with ASD, highlighting the significant role of both common and rare genetic mutations, as well as copy number variations (CNVs), single nucleotide polymorphisms (SNPs) and unique de novo variants. These genetic variations disrupt neurodevelopmental pathways, contributing to the disorder's complexity. Notably, CNVs are present in 10 %-20 % of individuals with autism, with 3 %-7 % detectable through cytogenetic methods. While the role of submicroscopic CNVs in ASD has been recently studied, their association with genomic loci and genes has not been thoroughly explored. In this review, we focus on 47 CNV regions linked to ASD, encompassing 1632 genes, including protein-coding genes and long non-coding RNAs (lncRNAs), of which 659 show significant brain expression. Using a list of ASD-associated genes from SFARI, we detect 17 regions harboring at least one known ASD-related protein-coding gene. Of the remaining 30 regions, we identify 24 regions containing at least one protein-coding gene with brain-enriched expression and a nervous system phenotype in mouse mutants, and one lncRNA with both brain-enriched expression and upregulation in iPSC to neuron differentiation. This review not only expands our understanding of the genetic diversity associated with ASD but also underscores the potential of lncRNAs in contributing to its etiology. Additionally, the discovered CNVs will be a valuable resource for future diagnostic, therapeutic, and research endeavors aimed at prioritizing genetic variations in ASD.
Collapse
Affiliation(s)
- Seyedeh Sedigheh Abedini
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; School of Biotechnology & Biomolecular Sciences, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Shiva Akhavantabasi
- Department of Molecular Biology and Genetics, Yeni Yuzyil University, Istanbul, Turkey; Ghiaseddin Jamshid Kashani University, Andisheh University Town, Danesh Blvd, 3441356611, Abyek, Qazvin, Iran
| | - Yuheng Liang
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia
| | - Julian Ik-Tsen Heng
- Curtin Health Innovation Research Institute, Curtin University, Bentley 6845, Australia
| | - Roohallah Alizadehsani
- Institute for Intelligent Systems Research and Innovation (IISRI), Deakin University, Victoria, Australia
| | - Iman Dehzangi
- Center for Computational and Integrative Biology, Rutgers University, Camden, NJ 08102, USA; Department of Computer Science, Rutgers University, Camden, NJ 08102, USA
| | - Denis C Bauer
- Transformational Bioinformatics, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Sydney, Australia; Applied BioSciences, Faculty of Science and Engineering, Macquarie University, Macquarie Park, Australia
| | - Hamid Alinejad-Rokny
- UNSW BioMedical Machine Learning Lab (BML), The Graduate School of Biomedical Engineering, UNSW Sydney, Sydney, NSW 2052, Australia; Tyree Institute of Health Engineering (IHealthE), UNSW Sydney, Sydney, NSW 2052, Australia.
| |
Collapse
|
3
|
Wang SE, Jiang YH. Novel epigenetic molecular therapies for imprinting disorders. Mol Psychiatry 2023; 28:3182-3193. [PMID: 37626134 PMCID: PMC10618104 DOI: 10.1038/s41380-023-02208-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2023] [Revised: 07/21/2023] [Accepted: 07/27/2023] [Indexed: 08/27/2023]
Abstract
Genomic imprinting disorders are caused by the disruption of genomic imprinting processes leading to a deficit or increase of an active allele. Their unique molecular mechanisms underlying imprinted genes offer an opportunity to investigate epigenetic-based therapy for reactivation of an inactive allele or reduction of an active allele. Current treatments are based on managing symptoms, not targeting the molecular mechanisms underlying imprinting disorders. Here, we highlight molecular approaches of therapeutic candidates in preclinical and clinical studies for individual imprinting disorders. These include the significant progress of discovery and testing of small molecules, antisense oligonucleotides, and CRISPR mediated genome editing approaches as new therapeutic strategies. We discuss the significant challenges of translating these promising therapies from the preclinical stage to the clinic, especially for genome editing based approaches.
Collapse
Affiliation(s)
- Sung Eun Wang
- Department of Genetics, Yale University School of Medicine, 333 Cedar street, New Haven, CT, 06520, USA
| | - Yong-Hui Jiang
- Department of Genetics, Yale University School of Medicine, 333 Cedar street, New Haven, CT, 06520, USA.
- Department of Neuroscience, Yale University School of Medicine, 333 Cedar street, New Haven, CT, 06520, USA.
- Department of Pediatrics, Yale University School of Medicine, 333 Cedar street, New Haven, CT, 06520, USA.
| |
Collapse
|
4
|
Liang D, Aygün N, Matoba N, Ideraabdullah FY, Love MI, Stein JL. Inference of putative cell-type-specific imprinted regulatory elements and genes during human neuronal differentiation. Hum Mol Genet 2023; 32:402-416. [PMID: 35994039 PMCID: PMC9851749 DOI: 10.1093/hmg/ddac207] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/02/2022] [Accepted: 08/17/2022] [Indexed: 01/24/2023] Open
Abstract
Genomic imprinting results in gene expression bias caused by parental chromosome of origin and occurs in genes with important roles during human brain development. However, the cell-type and temporal specificity of imprinting during human neurogenesis is generally unknown. By detecting within-donor allelic biases in chromatin accessibility and gene expression that are unrelated to cross-donor genotype, we inferred imprinting in both primary human neural progenitor cells and their differentiated neuronal progeny from up to 85 donors. We identified 43/20 putatively imprinted regulatory elements (IREs) in neurons/progenitors, and 133/79 putatively imprinted genes in neurons/progenitors. Although 10 IREs and 42 genes were shared between neurons and progenitors, most putative imprinting was only detected within specific cell types. In addition to well-known imprinted genes and their promoters, we inferred novel putative IREs and imprinted genes. Consistent with both DNA methylation-based and H3K27me3-based regulation of imprinted expression, some putative IREs also overlapped with differentially methylated or histone-marked regions. Finally, we identified a progenitor-specific putatively imprinted gene overlapping with copy number variation that is associated with uniparental disomy-like phenotypes. Our results can therefore be useful in interpreting the function of variants identified in future parent-of-origin association studies.
Collapse
Affiliation(s)
- Dan Liang
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nil Aygün
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Nana Matoba
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Folami Y Ideraabdullah
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Michael I Love
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Biostatistics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Jason L Stein
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- UNC Neuroscience Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| |
Collapse
|
5
|
Ku MS, Pan WC, Huang YT, Hsieh WS, Hsu YH, Chen PC, Liu CY. Associations between prenatal exposure to perfluoroalkyl substances, hypomethylation of MEST imprinted gene and birth outcomes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 304:119183. [PMID: 35331797 DOI: 10.1016/j.envpol.2022.119183] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 03/15/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Prenatal perfluoroalkyl substance (PFAS) exposure has been linked to adverse birth outcomes, but the underlying mechanism has yet to be elucidated. DNA methylation changes in mesoderm-specific transcript (MEST) imprinted gene may be a mechanism of the prenatal exposure effects of PFASs on fetal growth. The aim was to investigate the prenatal PFASs exposure effects on DNA methylation changes in MEST imprinted gene involved in fetal growth. Among 486 mother-infant pairs from the Taiwan Birth Panel Study, PFASs and DNA methylation levels at 5 CpG sites of MEST promoter region were measured in cord blood. Univariable and multivariable linear regressions were performed to estimate the associations between prenatal PFAS exposure, MEST DNA methylation levels, and child birth outcomes. Mediation analysis was performed to examine the potential pathway of MEST methylation between PFASs and birth outcomes. We found that higher prenatal perfluorooctyl sulfonate (PFOS) exposure was significantly associated with lower methylation levels at 5 CpG sites of MEST promoter region (an adjusted β range: -1.56, -2.22). Significant negative associations were also found between MEST methylation levels and child birth weight. Furthermore, the associations between PFOS and perfluorooctanoic acid (PFOA) exposure and MEST methylation levels were more profound in girls than in boys. The mediated effect of average MEST methylation level between PFOS exposure and birth weight was 18.3 (95% CI = 2.1, 40.2; p = 0.014). The direct effect of PFOS exposure to birth weight independent to average MEST methylation level was -93.2 (95% CI = -170.5, -17.8; p = 0.018). In conclusion, our results suggest that prenatal PFAS exposure, especially PFOS, is associated with lower methylation levels at MEST promoter region, which not only leverages the role of imprinted gene in ensuring the integrity of fetal growth but also provides a potential mechanism for evaluating the prenatal exposure effect.
Collapse
Affiliation(s)
- Mei-Sheng Ku
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan
| | - Wen-Chi Pan
- Institute of Environmental and Occupational Health Sciences, National Yang-Ming University, Taipei, Taiwan
| | - Yen-Tsung Huang
- Institute of Statistical Science, Academia Sinica, Taipei, Taiwan
| | - Wu-Shiun Hsieh
- Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Pediatrics, National Taiwan University College of Medicine and Hospital, Taipei, Taiwan
| | - Yi-Hsiang Hsu
- Hinda and Arthur Marcus Institute for Aging Research, Hebrew SeniorLife, Boston, MA, 02131, USA; Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, 02215, USA; Broad Institute of MIT and Harvard, Boston, MA, 02142, USA
| | - Pau-Chung Chen
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Environmental and Occupational Medicine, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan; National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli, Taiwan
| | - Chen-Yu Liu
- Institute of Environmental and Occupational Health Sciences, College of Public Health, National Taiwan University, Taipei, Taiwan; Department of Public Health, College of Public Health, National Taiwan University, Taipei, Taiwan.
| |
Collapse
|
6
|
Yu YL, Chen M, Zhu H, Zhuo MX, Chen P, Mao YJ, Li LY, Zhao Q, Wu M, Ye M. STAT1 epigenetically regulates LCP2 and TNFAIP2 by recruiting EP300 to contribute to the pathogenesis of inflammatory bowel disease. Clin Epigenetics 2021; 13:127. [PMID: 34112215 PMCID: PMC8194145 DOI: 10.1186/s13148-021-01101-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 05/10/2021] [Indexed: 12/23/2022] Open
Abstract
Background The aetiology of inflammatory bowel disease (IBD) is related to genetics and epigenetics. Epigenetic regulation of the pathogenesis of IBD has not been well defined. Here, we investigated the role of H3K27ac events in the pathogenesis of IBD. Based on previous ChIP-seq and RNA-seq assays, we studied signal transducer and activator of transcription 1 (STAT1) as a transcription factor (TF) and investigated whether the STAT1–EP300–H3K27ac axis contributes to the development of IBD. We performed ChIP-PCR to investigate the interaction between STAT1 and H3K27ac, and co-IP assays were performed to investigate the crosstalk between STAT1 and EP300. Results Lymphocyte cytosolic protein 2 (LCP2) and TNF-α‐inducible protein 2 (TNFAIP2) are target genes of STAT1. p-STAT1 binds to the enhancer loci of the two genes where H3K27ac is enriched, and EP300 subsequently binds to regulate their expression. In mice with dextran sulfate sodium (DSS)-induced acute colitis, an EP300 inhibitor significantly inhibited colitis. Conclusions p-STAT1 and EP300 promote TNFAIP2 and LCP2 expression through an increase in H3K27ac enrichment on their enhancers and contribute to the pathogenesis of chronic inflammation. Graphic abstract ![]()
Collapse
Affiliation(s)
- Ya-Li Yu
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Meng Chen
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Hua Zhu
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Ming-Xing Zhuo
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Ping Chen
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Yu-Juan Mao
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Lian-Yun Li
- Frontier Science Center for Immunology and Metabolism, Hubei Key Laboratory of Cell Homeostasis, Hubei Key Laboratory of Developmentally Originated Disease, Hubei Key Laboratory of Intestinal and Colorectal Diseases, College of Life Sciences, Wuhan University, Wuhan, 430072, Hubei, China
| | - Qiu Zhao
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China
| | - Min Wu
- Frontier Science Center for Immunology and Metabolism, Hubei Key Laboratory of Cell Homeostasis, Hubei Key Laboratory of Developmentally Originated Disease, Hubei Key Laboratory of Intestinal and Colorectal Diseases, College of Life Sciences, Wuhan University, Wuhan, 430072, Hubei, China
| | - Mei Ye
- Department of Gastroenterology, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China. .,Hubei Clinical Centre and Key Laboratory of Intestinal and Colorectal Diseases, Zhongnan Hospital, Wuhan University, Wuhan, 430071, Hubei, China.
| |
Collapse
|
7
|
DNA methylome signatures of prenatal exposure to synthetic glucocorticoids in hippocampus and peripheral whole blood of female guinea pigs in early life. Transl Psychiatry 2021; 11:63. [PMID: 33462183 PMCID: PMC7813870 DOI: 10.1038/s41398-020-01186-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Revised: 12/15/2020] [Accepted: 12/16/2020] [Indexed: 12/17/2022] Open
Abstract
Synthetic glucocorticoids (sGC) are administered to women at risk of preterm delivery, approximately 10% of all pregnancies. In animal models, offspring exposed to elevated glucocorticoids, either by administration of sGC or endogenous glucocorticoids as a result of maternal stress, show increased risk of developing behavioral, endocrine, and metabolic dysregulation. DNA methylation may play a critical role in long-lasting programming of gene regulation underlying these phenotypes. However, peripheral tissues such as blood are often the only accessible source of DNA for epigenetic analyses in humans. Here, we examined the hypothesis that prenatal sGC administration alters DNA methylation signatures in guinea pig offspring hippocampus and whole blood. We compared these signatures across the two tissue types to assess epigenetic biomarkers of common molecular pathways affected by sGC exposure. Guinea pigs were treated with sGC or saline in late gestation. Genome-wide modifications of DNA methylation were analyzed at single nucleotide resolution using reduced representation bisulfite sequencing in juvenile female offspring. Results indicate that there are tissue-specific as well as common methylation signatures of prenatal sGC exposure. Over 90% of the common methylation signatures associated with sGC exposure showed the same directionality of change in methylation. Among differentially methylated genes, 134 were modified in both hippocampus and blood, of which 61 showed methylation changes at identical CpG sites. Gene pathway analyses indicated that prenatal sGC exposure alters the methylation status of gene clusters involved in brain development. These data indicate concordance across tissues of epigenetic programming in response to alterations in glucocorticoid signaling.
Collapse
|
8
|
Gropman AL. Epigenetics and pervasive developmental disorders. EPIGENETICS IN PSYCHIATRY 2021:519-552. [DOI: 10.1016/b978-0-12-823577-5.00011-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2025]
|
9
|
Voronkov AV, Pozdnyakov DI. Neuroprotective Effect of L-carnitine. Focus on Changing Mitochondrial Function. RESEARCH RESULTS IN PHARMACOLOGY 2020. [DOI: 10.3897/rrpharmacology.6.57419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Introduction: In this study, the neuroprotective effect of L-carnitine administeredper osin a dose of 25 mg/kg – 800 mg/kg was evaluated. The effects of L-carnitine on changes in mitochondrial function were also studied.Materials and Methods: The neuroprotective effect and mitochondrial function were evaluated in a model of permanent focal ischemia in Wistar-line rats. L-carnitine was administered to rats orally for 72 hours from the moment of modeling ischemia. On the 4thday after the ischemia simulation, the change in the respiratory function of the mitochondria, the opening time of the mitochondrial permeability transition pore, the mitochondrial membrane potential, the concentration of intracellular calcium and the size of the cerebral necrosis zone were determined in rats’ brain supernatant.Results: As a result, it was found that the administration of L-carnitine contributed to the restoration of mitochondrial function and a decrease in the size of the brain necrosis zone. At the same time, the administration of L-carnitine in low doses (25 mg/kg – 100 mg/kg) did not have a significant effect on the change in the concentration of intracellular calcium. It should be noted that an increase in the dose of L-carnitine from 200 mg/kg to 800 mg/kg was not accompanied by a significant increase in the therapeutic effect.Discussion: L-carnitine is one of the key biomolecules that directly affect metabolic processes. It is known that L-carnitine acts as a ”shuttle” for long-chain fatty acids and thus can affect the alteration of mitochondrial function. However, the detailed nature of the mitochondriotropic action of L-carnitine has not been yet established. This was the focus of this study, which showed that the mitochondrion-oriented effect of L-carnitine is dose-dependent and expressed in the form of restoring the respiratory function of mitochondria, restoring the mitochondrial potential and increasing the latent opening time of the mitochondrial permeability transition pore, reducing the level of intracellular calcium.Conclusion: The study allowed us to expand our understanding of the L-carnitine neuroprotective effect and the effect of this compound on changes in mitochondrial function.Graphical abstract
Collapse
|
10
|
López-Tobón A, Trattaro S, Testa G. The sociability spectrum: evidence from reciprocal genetic copy number variations. Mol Autism 2020; 11:50. [PMID: 32546261 PMCID: PMC7298749 DOI: 10.1186/s13229-020-00347-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Accepted: 05/11/2020] [Indexed: 02/14/2023] Open
Abstract
Sociability entails some of the most complex behaviors processed by the central nervous system. It includes the detection, integration, and interpretation of social cues and elaboration of context-specific responses that are quintessentially species-specific. There is an ever-growing accumulation of molecular associations to autism spectrum disorders (ASD), from causative genes to endophenotypes across multiple functional layers; these however, have rarely been put in context with the opposite manifestation featured in hypersociability syndromes. Genetic copy number variations (CNVs) allow to investigate the relationships between gene dosage and its corresponding phenotypes. In particular, CNVs of the 7q11.23 locus, which manifest diametrically opposite social behaviors, offer a privileged window to look into the molecular substrates underlying the developmental trajectories of the social brain. As by definition sociability is studied in humans postnatally, the developmental fluctuations causing social impairments have thus far remained a black box. Here, we review key evidence of molecular players involved at both ends of the sociability spectrum, focusing on genetic and functional associations of neuroendocrine regulators and synaptic transmission pathways. We then proceed to propose the existence of a molecular axis centered around the paradigmatic dosage imbalances at the 7q11.23 locus, regulating networks responsible for the development of social behavior in humans and highlight the key role that neurodevelopmental models from reprogrammed pluripotent cells will play for its understanding.
Collapse
Affiliation(s)
- Alejandro López-Tobón
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy.
- Department of Oncology and Hemato-oncology, Università degli studi di Milano, Milan, Italy.
| | - Sebastiano Trattaro
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy.
- Department of Oncology and Hemato-oncology, Università degli studi di Milano, Milan, Italy.
| | - Giuseppe Testa
- Laboratory of Stem Cell Epigenetics, IEO, European Institute of Oncology, IRCCS, Milan, Italy.
- Department of Oncology and Hemato-oncology, Università degli studi di Milano, Milan, Italy.
- Human Technopole, Via Cristina Belgioioso 171, Milan, Italy.
| |
Collapse
|
11
|
Karami K, Zerehdaran S, Javadmanesh A, Shariati MM. Assessment of maternal and parent of origin effects in genetic variation of economic traits in Iranian native fowl. Br Poult Sci 2019; 60:486-492. [PMID: 31132866 DOI: 10.1080/00071668.2019.1621987] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
1. The objective of the study was to investigate the influence of maternal and parent of origin effects (POE) on genetic variation of Iranian native fowl on economic traits. 2. Studied traits were body weights at birth (BW0), at eight (BW8) and 12 weeks of age (BW12), age (ASM) and weight at sexual maturity (WSM), egg number (EN) and average egg weight (AEW). 3. Several models, including additive, maternal additive genetics, permanent environmental effects and POE were compared using Wombat software. Bayesian Information Criterion (BIC) was used to identify the best model for each trait. The chance of reranking of birds between models was investigated using Spearman correlation and Wilcoxon rank test. 4. Based on the best model, direct heritability estimates for BW0, BW8, BW12, ASM, WSM, EN and AEW traits were 0.05, 0.21, 0.23, 0.30, 0.39, 0.22 and 0.38, respectively. Proportion of variance due to paternal POE for BW8 was 4% and proportion of variance due to maternal POE for BW12 was 5%. 5. Estimated maternal heritability for BW0 was 0.30 and for BW8 and BW12 were 0.00 and 0.01, respectively, which shows that maternal heritability was reduced by age. 6. Based on the results, considering POE for BW8 and BW12 and maternal genetic effects for BW0 improved the accuracy of estimations and avoid reranking of birds for these traits.
Collapse
Affiliation(s)
- K Karami
- Department of Animal Science, Ferdowsi University of Mashhad , Mashhad , Iran
| | - S Zerehdaran
- Department of Animal Science, Ferdowsi University of Mashhad , Mashhad , Iran
| | - A Javadmanesh
- Department of Animal Science, Ferdowsi University of Mashhad , Mashhad , Iran
| | - M M Shariati
- Department of Animal Science, Ferdowsi University of Mashhad , Mashhad , Iran
| |
Collapse
|
12
|
Fattahi A, Latifi Z, Ghasemnejad T, Nejabati HR, Nouri M. Insights into in vitro spermatogenesis in mammals: Past, present, future. Mol Reprod Dev 2017; 84:560-575. [DOI: 10.1002/mrd.22819] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 04/03/2017] [Accepted: 04/17/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Amir Fattahi
- Institute for Stem Cell and Regenerative Medicine; Tabriz University of Medical Sciences; Tabriz Iran
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
| | - Zeinab Latifi
- Department of Clinical Biochemistry, Faculty of Medicine; Tabriz University of Medical Sciences; Tabriz Iran
| | - Tohid Ghasemnejad
- Women's Reproductive Health Research Center; Tabriz University of Medical Sciences; Tabriz Iran
| | - Hamid Reza Nejabati
- Women's Reproductive Health Research Center; Tabriz University of Medical Sciences; Tabriz Iran
| | - Mohammad Nouri
- Department of Reproductive Biology, Faculty of Advanced Medical Sciences; Tabriz University of Medical Sciences; Tabriz Iran
| |
Collapse
|
13
|
Smolkova B, El Yamani N, Collins AR, Gutleb AC, Dusinska M. Nanoparticles in food. Epigenetic changes induced by nanomaterials and possible impact on health. Food Chem Toxicol 2014; 77:64-73. [PMID: 25554528 DOI: 10.1016/j.fct.2014.12.015] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 12/17/2022]
Abstract
Disturbed epigenetic mechanisms, which developmentally regulate gene expression via modifications to DNA, histone proteins, and chromatin, have been hypothesized to play a key role in many human diseases. Recently it was shown that engineered nanoparticles (NPs), that already have a wide range of applications in various fields including food production, could dramatically affect epigenetic processes, while their ability to induce diseases remains poorly understood. Besides the obvious benefits of the new technologies, it is critical to assess their health effects before proceeding with industrial production. In this article, after surveying the applications of NPs in food technology, we review recent advances in the understanding of epigenetic pathological effects of NPs, and discuss their possible health impact with the aim of avoiding potential health risks posed by the use of nanomaterials in foods and food-packaging.
Collapse
Affiliation(s)
- Bozena Smolkova
- Department of Genetics, Cancer Research Institute of Slovak Academy of Sciences, Bratislava, Slovakia
| | - Naouale El Yamani
- Health Effects Laboratory, Department of Environmental Chemistry (MILK), NILU- Norwegian Institute for Air Research, 2027 Kjeller, Norway; Department of Nutrition, University of Oslo, Oslo, Norway
| | | | - Arno C Gutleb
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology (LIST), Luxembourg, Luxembourg
| | - Maria Dusinska
- Health Effects Laboratory, Department of Environmental Chemistry (MILK), NILU- Norwegian Institute for Air Research, 2027 Kjeller, Norway.
| |
Collapse
|
14
|
Hu M, TuanMu LC, Wei H, Gao F, Li L, Zhang S. Development and imprinted gene expression in uniparental preimplantation mouse embryos in vitro. Mol Biol Rep 2014; 42:345-53. [PMID: 25270250 DOI: 10.1007/s11033-014-3774-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2013] [Accepted: 09/20/2014] [Indexed: 01/15/2023]
Abstract
Increasing numbers of reports show that imprinted genes play a crucial role in fetal development, and uniparental embryos, which possess two paternally or two maternally derived pronuclei, are excellent tools for investigating the biological significance of imprinted genes. In the present study, to examine the in vitro developmental ability and expression pattern of eight imprinted genes in uniparental embryos, we produced androgenones, gynogenones, and parthenogenones using enucleation. Our data confirmed the previously observed restriction in haploid androgenetic development potential and first indicated that diploid androgenetic embryos were arrested in the 3/4-cell stage. Some imprinted genes were expressed in androgenetic, gynogenetic, and parthenogenetic blastocysts, suggesting that they were unable to maintain their imprinted expression status in uniparental embryos and that both paternal and maternal alleles are required for the specific expression of some imprinted genes.
Collapse
Affiliation(s)
- Minhua Hu
- Agricultural Animal Genomics and Molecular Breeding Key Lab of Guangdong Province, College of Animal Science, South China Agricultural University, Guangzhou, 510642, China
| | | | | | | | | | | |
Collapse
|
15
|
Li A, Meyre D. Jumping on the Train of Personalized Medicine: A Primer for Non-Geneticist Clinicians: Part 2. Fundamental Concepts in Genetic Epidemiology. ACTA ACUST UNITED AC 2014; 10:101-117. [PMID: 25598767 PMCID: PMC4287874 DOI: 10.2174/1573400510666140319235334] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2013] [Revised: 02/07/2014] [Accepted: 04/18/2014] [Indexed: 12/12/2022]
Abstract
With the decrease in sequencing costs, personalized genome sequencing will eventually become common in medical practice. We therefore write this series of three reviews to help non-geneticist clinicians to jump into the fast-moving field of personalized medicine. In the first article of this series, we reviewed the fundamental concepts in molecular genetics. In this second article, we cover the key concepts and methods in genetic epidemiology including the classification of genetic disorders, study designs and their implementation, genetic marker selection, genotyping and sequencing technologies, gene identification strategies, data analyses and data interpretation. This review will help the reader critically appraise a genetic association study. In the next article, we will discuss the clinical applications of genetic epidemiology in the personalized medicine area.
Collapse
Affiliation(s)
- Aihua Li
- Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON L8N 3Z5, Canada
| | - David Meyre
- Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON L8N 3Z5, Canada
| |
Collapse
|
16
|
Epigenetic analysis of neurocognitive development at 1 year of age in a community-based pregnancy cohort. Behav Genet 2014; 44:113-25. [PMID: 24452678 DOI: 10.1007/s10519-014-9641-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2013] [Accepted: 01/09/2014] [Indexed: 10/25/2022]
Abstract
Multiple studies show that molecular genetic changes and epigenetic modifications affect the risk of cognitive disability or impairment. However, the role of epigenetic variation in cognitive development of neurotypical young children remains largely unknown. Using data from a prospective, community-based study of mother-infant pairs, we investigated the association of DNA methylation patterns in neonatal umbilical cord blood with cognitive and language development at 1 year of age. No CpG loci achieved genome-wide significance, although a small number of weakly suggestive associations with Bayley-III Receptive Communication scales were noted. While umbilical cord blood is a convenient resource for genetic analyses of birth outcomes, our results do not provide conclusive evidence that its use for DNA methylation profiling yields epigenetic markers that are directly related to postnatal neurocognitive outcomes at 1 year of age.
Collapse
|
17
|
Hu M, Zhao Z, TuanMu LC, Wei H, Gao F, Li L, Ying J, Zhang S. Analysis of imprinted gene expression and implantation in haploid androgenetic mouse embryos. Andrologia 2014; 47:102-8. [PMID: 24387305 DOI: 10.1111/and.12222] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2013] [Indexed: 11/27/2022] Open
Abstract
The successful development of mammalian embryos requires both parental genomes. Nuclear transfer techniques have been adapted to generate uniparental embryos, which possess two sets of paternal or maternal genomes. These embryos fail to develop to term because of abnormal imprinted gene expression, which is not regulated by Mendelian inheritance. Uniparental embryos provide us with an important model to investigate imprinted gene function and ontogenesis. To evaluate the pre- and post-developmental ability of haploid androgenetic mouse embryos, and to analyse the expression of imprinted genes Igf2r, Asb4 and Mest in haploid androgenetic/gynogenetic blastocysts, we produced the haploid mouse embryos using the enucleation technique, examined their development at 6.5 dpc and quantified gene expression by quantitative real-time PCR. The results demonstrated that the developmental potential of haploid embryos was severely impaired and revealed that the haploid androgenones could induce the deciduas reaction, but failed to retain a live foetus at 6.5 dpc. Expression of imprinted genes Igf2r and Asb4 was unregulated in haploid androgenetic/gynogenetic blastocysts.
Collapse
Affiliation(s)
- M Hu
- Agricultural Animal Genomics and Molecular Breeding Key Lab of Guangdong Province, College of Animal Science, South China Agricultural University, Guangzhou, China; Guangzhou General Pharmaceutical Research Institute Co., Ltd., Guangzhou, China
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Gropman AL. Epigenetics and Pervasive Developmental Disorders. EPIGENETICS IN PSYCHIATRY 2014:395-424. [DOI: 10.1016/b978-0-12-417114-5.00019-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2025]
|
19
|
Flashner BM, Russo ME, Boileau JE, Leong DW, Gallicano GI. Epigenetic factors and autism spectrum disorders. Neuromolecular Med 2013; 15:339-50. [PMID: 23468062 DOI: 10.1007/s12017-013-8222-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Accepted: 02/13/2013] [Indexed: 12/28/2022]
Abstract
Autism is a complex neurodevelopmental disorder that has significant phenotypic overlap with several diseases, many of which fall within the broader category of autism spectrum disorders (ASDs). The etiology of the disorder is unclear and seems to involve a complex interplay of polygenic as well as environmental factors. We discuss evidence that suggests that epigenetic dysregulation is highly implicated as a contributing cause of ASDs and autism. Specifically, we examine neurodevelopmental disorders that share significant phenotypic overlap with ASDs and feature the dysregulation of epigenetically modified genes including UBE3A, GABA receptor genes, and RELN. We then look at the dysregulated expression of implicated epigenetic modifiers, namely MeCP2, that yield complex and varied downstream pleiotropic effects. Finally, we examine epigenetically mediated parent-of-origin effects through which paternal gene expression dominates that of maternal contributing to contrasting phenotypes implicated in ASDs. Such preliminary evidence suggests that elucidating the complex role of epigenetic regulations involved in ASDs could prove vital in furthering our understanding of the complex etiology of autism and ASDs.
Collapse
Affiliation(s)
- Bess M Flashner
- Department of Biochemistry and Molecular and Cellular Biology, Georgetown University School of Medicine, 3900 Reservoir Rd. NW, Washington, DC 20057, USA
| | | | | | | | | |
Collapse
|
20
|
Relton CL, Groom A, St. Pourcain B, Sayers AE, Swan DC, Embleton ND, Pearce MS, Ring SM, Northstone K, Tobias JH, Trakalo J, Ness AR, Shaheen SO, Davey Smith G. DNA methylation patterns in cord blood DNA and body size in childhood. PLoS One 2012; 7:e31821. [PMID: 22431966 PMCID: PMC3303769 DOI: 10.1371/journal.pone.0031821] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 01/16/2012] [Indexed: 12/18/2022] Open
Abstract
Background Epigenetic markings acquired in early life may have phenotypic consequences later in development through their role in transcriptional regulation with relevance to the developmental origins of diseases including obesity. The goal of this study was to investigate whether DNA methylation levels at birth are associated with body size later in childhood. Principal Findings A study design involving two birth cohorts was used to conduct transcription profiling followed by DNA methylation analysis in peripheral blood. Gene expression analysis was undertaken in 24 individuals whose biological samples and clinical data were collected at a mean ± standard deviation (SD) age of 12.35 (0.95) years, the upper and lower tertiles of body mass index (BMI) were compared with a mean (SD) BMI difference of 9.86 (2.37) kg/m2. This generated a panel of differentially expressed genes for DNA methylation analysis which was then undertaken in cord blood DNA in 178 individuals with body composition data prospectively collected at a mean (SD) age of 9.83 (0.23) years. Twenty-nine differentially expressed genes (>1.2-fold and p<10−4) were analysed to determine DNA methylation levels at 1–3 sites per gene. Five genes were unmethylated and DNA methylation in the remaining 24 genes was analysed using linear regression with bootstrapping. Methylation in 9 of the 24 (37.5%) genes studied was associated with at least one index of body composition (BMI, fat mass, lean mass, height) at age 9 years, although only one of these associations remained after correction for multiple testing (ALPL with height, pCorrected = 0.017). Conclusions DNA methylation patterns in cord blood show some association with altered gene expression, body size and composition in childhood. The observed relationship is correlative and despite suggestion of a mechanistic epigenetic link between in utero life and later phenotype, further investigation is required to establish causality.
Collapse
Affiliation(s)
- Caroline L. Relton
- HNRC, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Alexandra Groom
- HNRC, Institute of Genetic Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
- * E-mail:
| | - Beate St. Pourcain
- MRC Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, United Kingdom
| | - Adrian E. Sayers
- Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Daniel C. Swan
- Bioinformatic Support Unit, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Nicholas D. Embleton
- Newcastle Neonatal Service, Royal Victoria Infirmary, Newcastle upon Tyne, United Kingdom
- Institute of Health and Society, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Mark S. Pearce
- Institute of Health and Society, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Susan M. Ring
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Kate Northstone
- MRC Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, United Kingdom
| | - Jon H. Tobias
- Musculoskeletal Research Unit, School of Clinical Sciences, University of Bristol, Bristol, United Kingdom
| | - Joseph Trakalo
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Andy R. Ness
- School of Dental Sciences, University of Bristol, Bristol, United Kingdom
| | - Seif O. Shaheen
- Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
| | - George Davey Smith
- MRC Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, United Kingdom
| |
Collapse
|
21
|
Characterization, tissue expression, and imprinting analysis of the porcine CDKN1C and NAP1L4 genes. J Biomed Biotechnol 2012; 2012:946527. [PMID: 22500112 PMCID: PMC3303864 DOI: 10.1155/2012/946527] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2011] [Revised: 10/25/2011] [Accepted: 11/15/2011] [Indexed: 01/07/2023] Open
Abstract
CDKN1C and NAP1L4 in human CDKN1C/KCNQ1OT1 imprinted domain are two key candidate genes responsible for BWS (Beckwith-Wiedemann syndrome) and cancer. In order to increase understanding of these genes in pigs, their cDNAs are characterized in this paper. By the IMpRH panel, porcine CDKN1C and NAP1L4 genes were assigned to porcine chromosome 2, closely linked with IMpRH06175 and with LOD of 15.78 and 17.94, respectively. By real-time quantitative RT-PCR and polymorphism-based method, tissue and allelic expression of both genes were determined using F1 pigs of Rongchang and Landrace reciprocal crosses. The transcription levels of porcine CDKN1C and NAP1L4 were significantly higher in placenta than in other neonatal tissues (P < 0.01) although both genes showed the highest expression levels in the lung and kidney of one-month pigs (P < 0.01). Imprinting analysis demonstrated that in pigs, CDKN1C was maternally expressed in neonatal heart, tongue, bladder, ovary, spleen, liver, skeletal muscle, stomach, small intestine, and placenta and biallelically expressed in lung and kidney, while NAP1L4 was biallelically expressed in the 12 neonatal tissues examined. It is concluded that imprinting of CDKN1C is conservative in mammals but has tissue specificity in pigs, and imprinting of NAP1L4 is controversial in mammalian species.
Collapse
|
22
|
Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation. Asian J Androl 2012; 14:436-50. [PMID: 22367183 DOI: 10.1038/aja.2011.160] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 (EZH2) overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 (IGF2). A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.
Collapse
|
23
|
Saito J, Hirota T, Kikunaga N, Otsubo K, Ieiri I. Interindividual differences in placental expression of the SLC22A2 (OCT2) gene: relationship to epigenetic variations in the 5'-upstream regulatory region. J Pharm Sci 2011; 100:3875-83. [PMID: 21523786 DOI: 10.1002/jps.22595] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Revised: 04/04/2011] [Accepted: 04/12/2011] [Indexed: 01/13/2023]
Abstract
Organic cation transporters (OCTs) mediate the transport of organic cations and some drugs (e.g., metformin and cimetidine). OCT1, OCT2, and OCT3 are located in the imprinting cluster of the insulin-like growth factor 2 receptor. It has been reported that OCT1 and OCT3 show a biallelic expression, whereas OCT2 undergoes maternal imprinting in the human placenta; however, a loss of the imprinting of OCT2 has recently been reported in some placental samples. This study investigated whether epigenetic mechanisms are involved in interindividual differences in the placental expression of OCT2. Because OCT2 mRNA levels were higher in biallelic samples than that in monoallelic samples, we compared the DNA methylation and chromatin modifications in the promoter regions. There was no remarkable difference in DNA methylation between the mono allelic samples and biallelic samples. In contrast, histone H3 acetylation (H3Ac) was increased in the biallelic samples. A significant negative correlation was observed between the trimethylation of lysine-9 on histone H3 (H3K9me3) and the OCT2 mRNA levels. Our results suggest that H3Ac plays a role in the allelic expression of OCT2. In addition, H3K9me3 in the OCT2 promoter may explain the interindividual differences in placental OCT2 mRNA levels.
Collapse
Affiliation(s)
- Jumpei Saito
- Department of Clinical Pharmacokinetics, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 8128582, Japan
| | | | | | | | | |
Collapse
|
24
|
Abstract
As part of the PLoS Epigenetics Collection, Caroline Relton and George Davey Smith discuss the potential of epigenetics for the treatment and prevention of common complex diseases, including cancer.
Collapse
Affiliation(s)
- Caroline L Relton
- Human Nutrition Research Centre, Institute of Human Genetics, Newcastle University, Newcastle upon Tyne, United Kingdom.
| | | |
Collapse
|
25
|
Epigenetics, copy number variation, and other molecular mechanisms underlying neurodevelopmental disabilities: new insights and diagnostic approaches. J Dev Behav Pediatr 2010; 31:582-91. [PMID: 20814257 DOI: 10.1097/dbp.0b013e3181ee384e] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The diagnostic evaluation of children with intellectual disability (ID) and other neurodevelopmental disabilities (NDD) has become increasingly complex in recent years owing to a number of newly recognized genetic mechanisms and sophisticated methods to diagnose them. Previous studies have attempted to address the diagnostic yield of finding a genetic cause in ID. The results have varied widely from 10% to 81%, with the highest percentage being found in studies using new array comparative genomic hybridization methodology especially in autism. Although many cases of ID/NDD result from chromosomal aneuploidy or structural rearrangements, single gene disorders and new categories of genome modification, including epigenetics and copy number variation play an increasingly important role in diagnosis and testing. Epigenetic mechanisms, such as DNA methylation and modifications to histone proteins, regulate high-order DNA structure and gene expression. Aberrant epigenetic and copy number variation mechanisms are involved in several neurodevelopmental and neurodegenerative disorders including Rett syndrome, fragile X syndrome, and microdeletion syndromes. This review will describe a number of the molecular genetic mechanisms that play a role in disorders leading to ID/NDD and will discuss the categories and technologies for diagnostic testing of these conditions.
Collapse
|
26
|
Hager R, Cheverud JM, Leamy LJ, Wolf JB. Sex dependent imprinting effects on complex traits in mice. BMC Evol Biol 2008; 8:303. [PMID: 18976474 PMCID: PMC2605465 DOI: 10.1186/1471-2148-8-303] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2008] [Accepted: 10/31/2008] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND Genomic imprinting is an epigenetic source of variation in quantitative traits that results from monoallelic gene expression, where commonly either only the paternally- or the maternally-derived allele is expressed. Imprinting has been shown to affect a diversity of complex traits in a variety of species. For several such quantitative traits sex-dependent genetic effects have been discovered, but whether imprinting effects also show such sex-dependence has yet to be explored. Moreover, theoretical work on the evolution of sex-dependent genomic imprinting effects makes specific predictions about the phenotypic patterns of such effects, which, however, have not been assessed empirically to date. RESULTS Using a genome-scan for loci affecting a set of complex growth and body composition traits from an intercross between two divergent mouse strains, we investigated possible sex-dependent imprinting effects. Our results demonstrate for the first time the existence of genomic imprinting effects that depend on sex and are not related to sex-chromosome effects. We detected a total of 13 loci on 11 chromosomes that showed significant differences between the sexes in imprinting effects. Most loci showed imprinting effects in only one sex, with eight imprinted effects found in males and six in females. One locus showed sex-dependent imprinting effects in both sexes for different traits. The absence of an imprinting effect in one sex was not necessarily indicative of the overall inactivity of the locus in that sex, as for several loci a significant additive or dominance effect was detected. Moreover, three loci exhibited significant additive effects in both sexes but their imprinting effect was restricted to one sex. CONCLUSION Our results clearly show that imprinting effects can be sex-dependent and also suggest that new candidate imprinted loci can be detected when taking account of sex-specific imprinting effects. However, predictions made about the evolution of sex-dependent imprinting effects and associated phenotypic patterns cannot be unequivocally supported at present and further research into the selection pressures applied to the strains of mice used in our study is required.
Collapse
Affiliation(s)
- Reinmar Hager
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| | - James M Cheverud
- Department of Anatomy and Neurobiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Larry J Leamy
- Department of Biology, University of North Carolina at Charlotte, Charlotte, North Carolina 28223, USA
| | - Jason B Wolf
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
| |
Collapse
|
27
|
Crespi B. Genomic imprinting in the development and evolution of psychotic spectrum conditions. Biol Rev Camb Philos Soc 2008; 83:441-93. [PMID: 18783362 DOI: 10.1111/j.1469-185x.2008.00050.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
I review and evaluate genetic and genomic evidence salient to the hypothesis that the development and evolution of psychotic spectrum conditions have been mediated in part by alterations of imprinted genes expressed in the brain. Evidence from the genetics and genomics of schizophrenia, bipolar disorder, major depression, Prader-Willi syndrome, Klinefelter syndrome, and other neurogenetic conditions support the hypothesis that the etiologies of psychotic spectrum conditions commonly involve genetic and epigenetic imbalances in the effects of imprinted genes, with a bias towards increased relative effects from imprinted genes with maternal expression or other genes favouring maternal interests. By contrast, autistic spectrum conditions, including Kanner autism, Asperger syndrome, Rett syndrome, Turner syndrome, Angelman syndrome, and Beckwith-Wiedemann syndrome, commonly engender increased relative effects from paternally expressed imprinted genes, or reduced effects from genes favouring maternal interests. Imprinted-gene effects on the etiologies of autistic and psychotic spectrum conditions parallel the diametric effects of imprinted genes in placental and foetal development, in that psychotic spectrum conditions tend to be associated with undergrowth and relatively-slow brain development, whereas some autistic spectrum conditions involve brain and body overgrowth, especially in foetal development and early childhood. An important role for imprinted genes in the etiologies of psychotic and autistic spectrum conditions is consistent with neurodevelopmental models of these disorders, and with predictions from the conflict theory of genomic imprinting.
Collapse
Affiliation(s)
- Bernard Crespi
- Department of Biosciences, Simon Fraser University, Burnaby BCV5A1S6, Canada.
| |
Collapse
|
28
|
Leamy LJ, Klingenberg CP, Sherratt E, Wolf JB, Cheverud JM. A search for quantitative trait loci exhibiting imprinting effects on mouse mandible size and shape. Heredity (Edinb) 2008; 101:518-26. [PMID: 18685568 DOI: 10.1038/hdy.2008.79] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Genomic imprinting refers to the pattern of monoallelic parent-of-origin-dependent gene expression where one of the two alleles at a locus is expressed and the other silenced. Although some genes in mice are known to be imprinted, the true scope of imprinting and its impact on the genetic architecture of a wide range of morphometric traits is mostly unknown. We therefore searched for quantitative trait loci (QTL) exhibiting imprinting effects on mandible size and shape traits in a large F(3) population of mice originating from an intercross of the LG/J (Large) and SM/J (Small) inbred strains. We discovered a total of 51 QTL affecting mandible size and shape, 6 of which exhibited differences between reciprocal heterozygotes, the usual signature of imprinting effects. However, our analysis showed that only one of these QTL (affecting mandible size) exhibited a pattern consistent with true imprinting effects, whereas reciprocal heterozygote differences in the other five all were due to maternal genetic effects. We concluded that genomic imprinting has a negligible effect on these specific morphometric traits, and that maternal genetic effects may account for many of the previously reported instances of apparent genomic imprinting.
Collapse
Affiliation(s)
- L J Leamy
- Department of Biology, University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
| | | | | | | | | |
Collapse
|
29
|
Wolf JB, Cheverud JM, Roseman C, Hager R. Genome-wide analysis reveals a complex pattern of genomic imprinting in mice. PLoS Genet 2008; 4:e1000091. [PMID: 18535661 PMCID: PMC2390766 DOI: 10.1371/journal.pgen.1000091] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2008] [Accepted: 05/08/2008] [Indexed: 11/23/2022] Open
Abstract
Parent-of-origin–dependent gene expression resulting from genomic imprinting plays an important role in modulating complex traits ranging from developmental processes to cognitive abilities and associated disorders. However, while gene-targeting techniques have allowed for the identification of imprinted loci, very little is known about the contribution of imprinting to quantitative variation in complex traits. Most studies, furthermore, assume a simple pattern of imprinting, resulting in either paternal or maternal gene expression; yet, more complex patterns of effects also exist. As a result, the distribution and number of different imprinting patterns across the genome remain largely unexplored. We address these unresolved issues using a genome-wide scan for imprinted quantitative trait loci (iQTL) affecting body weight and growth in mice using a novel three-generation design. We identified ten iQTL that display much more complex and diverse effect patterns than previously assumed, including four loci with effects similar to the callipyge mutation found in sheep. Three loci display a new phenotypic pattern that we refer to as bipolar dominance, where the two heterozygotes are different from each other while the two homozygotes are identical to each other. Our study furthermore detected a paternally expressed iQTL on Chromosome 7 in a region containing a known imprinting cluster with many paternally expressed genes. Surprisingly, the effects of the iQTL were mostly restricted to traits expressed after weaning. Our results imply that the quantitative effects of an imprinted allele at a locus depend both on its parent of origin and the allele it is paired with. Our findings also show that the imprinting pattern of a locus can be variable over ontogenetic time and, in contrast to current views, may often be stronger at later stages in life. For certain genes, individuals express only the copy of the gene they inherit from either their mother (“maternally expressed” genes) or their father (“paternally expressed” genes). This “parent-of-origin–dependent” pattern of gene expression is known as genomic imprinting and has been shown to play an important role in modulating a variety of traits ranging from developmental processes to cognitive abilities and associated disorders. While various molecular techniques have allowed for the identification of many imprinted genes, very little is known about the contribution of imprinting to variation seen among individuals in continuously varying traits such as body size. Here we address this issue by using a genome-wide analysis aimed at finding regions of the genome that show an effect of imprinting on body weight and growth in mice. We identified ten loci that displayed complex and diverse patterns of effect, including four loci with effects similar to the unusual callipyge mutation found in sheep and three that displayed a new phenotypic pattern that we refer to as bipolar dominance. Surprisingly, most imprinting effects were strongest during the post-weaning period, and many showed shifts in the pattern of imprinting over ontogenetic time.
Collapse
Affiliation(s)
- Jason B Wolf
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
| | | | | | | |
Collapse
|
30
|
Maternal effects as the cause of parent-of-origin effects that mimic genomic imprinting. Genetics 2008; 178:1755-62. [PMID: 18245362 DOI: 10.1534/genetics.107.080697] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Epigenetic effects are increasingly recognized as an important source of variation in complex traits and have emerged as the focus of a rapidly expanding area of research. Principle among these effects is genomic imprinting, which has generally been examined in analyses of complex traits by testing for parent-of-origin-dependent effects of alleles. However, in most of these analyses maternal effects are confounded with genomic imprinting because they can produce the same patterns of phenotypic variation expected for various forms of imprinting. Distinguishing between the two is critical for genetic and evolutionary studies because they have entirely different patterns of gene expression and evolutionary dynamics. Using a simple single-locus model, we show that maternal genetic effects can result in patterns that mimic those expected under genomic imprinting. We further demonstrate how maternal effects and imprinting effects can be distinguished using genomic data from parents and offspring. The model results are applied to a genome scan for quantitative trait loci (QTL) affecting growth- and weight-related traits in mice to illustrate how maternal effects can mimic imprinting. This genome scan revealed five separate maternal-effect loci that caused a diversity of patterns mimicking those expected under various modes of genomic imprinting. These results demonstrate that the appearance of parent-of-origin-dependent effects (POEs) of alleles at a locus cannot be taken as direct evidence that the locus is imprinted. Moreover, they show that, in gene mapping studies, genetic data from both parents and offspring are required to successfully differentiate between imprinting and maternal effects as the cause of apparent parent-of-origin effects of alleles.
Collapse
|
31
|
Smith AC, Shuman C, Chitayat D, Steele L, Ray PN, Bourgeois J, Weksberg R. Severe presentation of Beckwith-Wiedemann syndrome associated with high levels of constitutional paternal uniparental disomy for chromosome 11p15. Am J Med Genet A 2008; 143A:3010-5. [PMID: 18000906 DOI: 10.1002/ajmg.a.32030] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Beckwith-Wiedemann syndrome (BWS) is an overgrowth syndrome characterized by macrosomia, macroglossia, omphalocele, hemihyperplasia, and increased tumor risk. BWS can be associated with genetic and/or epigenetic alterations that modify imprinted gene expression on chromosome 11p15.5. Somatic mosaicism for paternal uniparental disomy (UPD) of chromosome 11p15, found in 20% of BWS patients, is associated with specific features of BWS including hemihyperplasia, Wilms tumor, and hepatoblastoma. The highly variable phenotypic spectrum of BWS associated with UPD may well reflect the level of UPD 11 cells in specific organs and tissues such that very high levels of UPD might produce a more severe phenotypic expression of BWS. In this regard we report on two patients with severe presentations of BWS and extremely high levels of UPD in DNA from lymphocytes. Clinically, both patients demonstrated extreme macroglossia, persistent hypoglycemia, cardiomyopathy, hemihyperplasia, renal abnormalities, abdominal organomegaly, hepatoblastoma and died in the first 6 months of life. These two patients support the hypothesis that high levels of UPD define high expressivity in BWS.
Collapse
Affiliation(s)
- Adam C Smith
- Institute of Medical Science, University of Toronto, Toronto, Canada
| | | | | | | | | | | | | |
Collapse
|
32
|
Abstract
Turner syndrome is a neurogenetic disorder characterized by partial or complete monosomy-X. It is associated with certain physical and medical features, including estrogen deficiency, short stature, and increased risk for several diseases, with cardiac conditions being among the most serious. The cognitive-behavioral phenotype associated with the syndrome includes strengths in verbal domains with impairments in visuospatial, executive function, and emotion processing. Less is known regarding psychosocial and psychiatric functioning in Turner syndrome, but essential aspects of psychotherapeutic treatment plans are suggested. Future investigations should include continued genetic studies and determination of candidate genes for physical and cognitive features. Multimodal, interdisciplinary studies are essential for identifying optimal, syndrome-specific interventions for improving the lives of individuals who have Turner syndrome.
Collapse
Affiliation(s)
- Shelli R Kesler
- Department of Psychiatry and Behavioral Sciences, Stanford University, MC5795, Stanford, CA 94305-5795, USA.
| |
Collapse
|
33
|
Abstract
Imprinted genes comprise a small subset of the genome whose epigenetic reprogramming in the germ line is necessary for subsequent normal embryonic development. This reprogramming and resetting of the imprints, through an erasure/acquisition/maintenance cycle, is a subtle and tightly orchestrated phenomenon, involving specific genomic regions and methylation enzymes. Dysregulation of imprinted genes has indeed been shown to lead to several human disorders as well as to affect placental and fetal growth. There have been numerous and conflicting studies assessing the possible association of imprinting disorders with assisted reproductive techniques. This work analyzes all relevant and available reports with regard to the association between assisted reproductive techniques and imprinting disorders. It also discusses whether this possibly increased risk of imprinting disorders may be linked to specific steps of these reproductive techniques or already present in the gametes of infertile patients. A better understanding of epigenetic reprogramming in the germ line is absolutely necessary both to assess the safety of these methods and of the use of impaired spermatogenesis gametes for assisted reproduction.
Collapse
Affiliation(s)
- Ariane Paoloni-Giacobino
- Department of Genetic Medicine and Development, University of Geneva Medical School, Switzerland.
| |
Collapse
|
34
|
Schumacher A, Petronis A. Epigenetics of Complex Diseases: From General Theory to Laboratory Experiments. Curr Top Microbiol Immunol 2006; 310:81-115. [PMID: 16909908 DOI: 10.1007/3-540-31181-5_6] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Despite significant effort, understanding the causes and mechanisms of complex non-Mendelian diseases remains a key challenge. Although numerous molecular genetic linkage and association studies have been conducted in order to explain the heritable predisposition to complex diseases, the resulting data are quite often inconsistent and even controversial. In a similar way, identification of environmental factors causal to a disease is difficult. In this article, a new interpretation of the paradigm of "genes plus environment" is presented in which the emphasis is shifted to epigenetic misregulation as a major etiopathogenic factor. Epigenetic mechanisms are consistent with various non-Mendelian irregularities of complex diseases, such as the existence of clinically indistinguishable sporadic and familial cases, sexual dimorphism, relatively late age of onset and peaks of susceptibility to some diseases, discordance of monozygotic twins and major fluctuations on the course of disease severity. It is also suggested that a substantial portion of phenotypic variance that traditionally has been attributed to environmental effects may result from stochastic epigenetic events in the cell. It is argued that epigenetic strategies, when applied in parallel with the traditional genetic ones, may significantly advance the discovery of etiopathogenic mechanisms of complex diseases. The second part of this chapter is dedicated to a review of laboratory methods for DNA methylation analysis, which may be useful in the study of complex diseases. In this context, epigenetic microarray technologies are emphasized, as it is evident that such technologies will significantly advance epigenetic analyses in complex diseases.
Collapse
Affiliation(s)
- A Schumacher
- The Krembil Family Epigenetics Laboratory, Centre for Addiction and Mental Health, ON, Toronto, Canada
| | | |
Collapse
|
35
|
Badcock C, Crespi B. Imbalanced genomic imprinting in brain development: an evolutionary basis for the aetiology of autism. J Evol Biol 2006; 19:1007-32. [PMID: 16780503 DOI: 10.1111/j.1420-9101.2006.01091.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We describe a new hypothesis for the development of autism, that it is driven by imbalances in brain development involving enhanced effects of paternally expressed imprinted genes, deficits of effects from maternally expressed genes, or both. This hypothesis is supported by: (1) the strong genomic-imprinting component to the genetic and developmental mechanisms of autism, Angelman syndrome, Rett syndrome and Turner syndrome; (2) the core behavioural features of autism, such as self-focused behaviour, altered social interactions and language, and enhanced spatial and mechanistic cognition and abilities, and (3) the degree to which relevant brain functions and structures are altered in autism and related disorders. The imprinted brain theory of autism has important implications for understanding the genetic, epigenetic, neurological and cognitive bases of autism, as ultimately due to imbalances in the outcomes of intragenomic conflict between effects of maternally vs. paternally expressed genes.
Collapse
Affiliation(s)
- C Badcock
- Department of Sociology, London School of Economics, London, UK
| | | |
Collapse
|
36
|
Chelly J, Khelfaoui M, Francis F, Chérif B, Bienvenu T. Genetics and pathophysiology of mental retardation. Eur J Hum Genet 2006; 14:701-13. [PMID: 16721406 DOI: 10.1038/sj.ejhg.5201595] [Citation(s) in RCA: 188] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/08/2022] Open
Abstract
Mental retardation (MR) is defined as an overall intelligence quotient lower than 70, associated with functional deficit in adaptive behavior, such as daily-living skills, social skills and communication. Affecting 1-3% of the population and resulting from extraordinary heterogeneous environmental, chromosomal and monogenic causes, MR represents one of the most difficult challenges faced today by clinician and geneticists. Detailed analysis of the Online Mendelian Inheritance in Man database and literature searches revealed more than a thousand entries for MR, and more than 290 genes involved in clinical phenotypes or syndromes, metabolic or neurological disorders characterized by MR. We estimate that many more MR genes remain to be identified. The purpose of this review is to provide an overview on the remarkable progress achieved over the last decade in delineating genetic causes of MR, and to highlight the emerging biological and cellular processes and pathways underlying pathogeneses of human cognitive disorders.
Collapse
Affiliation(s)
- Jamel Chelly
- Institut Cochin, Inserm-U567, CNRS-UMR 8104, Université Paris 5 René Descartes, Faculté de Médecine René Descartes, Paris, France.
| | | | | | | | | |
Collapse
|
37
|
Normark BB. PERSPECTIVE: MATERNAL KIN GROUPS AND THE ORIGINS OF ASYMMETRIC GENETIC SYSTEMS?GENOMIC IMPRINTING, HAPLODIPLOIDY, AND PARTHENOGENESIS. Evolution 2006. [DOI: 10.1111/j.0014-3820.2006.tb01145.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
38
|
Abstract
Recent years have brought a dramatic change in our understanding of the role of ribonucleic acids (RNAs) within the cell. In addition to the already well-known classes of RNAs that take part in the transmission of genetic information from DNA to proteins, a new highly heterogeneous group of RNA molecules has emerged. The regulatory nonprotein-coding RNAs (npcRNAs) have been shown to be involved in modulation of gene expression on both the transcriptional and post-transcriptional level. They participate in mechanisms of chromatin modification, regulation of transcription factor activity, and influencing mRNA stability, processing, and translation. npcRNAs are key factors in genetic imprinting, dosage compensation of X-chromosome-linked genes, and many processes of differentiation and development.
Collapse
Affiliation(s)
- M Szymański
- Institute of Bioorganic Chemistry of the Polish Academy of Sciences, Noskowskiego 12, 61-704 Poznan, Poland.
| | | |
Collapse
|
39
|
Normark BB. PERSPECTIVE: MATERNAL KIN GROUPS AND THE ORIGINS OF ASYMMETRIC GENETIC SYSTEMS—GENOMIC IMPRINTING, HAPLODIPLOIDY, AND PARTHENOGENESIS. Evolution 2006. [DOI: 10.1554/05-546.1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
40
|
Szymanski M, Barciszewska MZ, Erdmann VA, Barciszewski J. A new frontier for molecular medicine: noncoding RNAs. Biochim Biophys Acta Rev Cancer 2005; 1756:65-75. [PMID: 16125325 DOI: 10.1016/j.bbcan.2005.07.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Revised: 07/27/2005] [Accepted: 07/28/2005] [Indexed: 02/06/2023]
Abstract
It is now becoming evident that the variety of noncoding RNA (ncRNA) molecules play important roles in many cellular processes and they are not just mere intermediates in transfer of genetic information from DNA to proteins. Recent data, from the analyses of transcriptional activity of human genome, suggest that it may contain roughly equal numbers of protein- and RNA-encoding transcription units. Many of the ncRNAs described in humans as well as in other mammals have been linked, through specific chromosomal localization or expression patterns, with certain diseases including complex congenital syndromes, neurobehavioral and developmental disorders and cancer. These findings clearly indicate that an expression of genes of which end-products are RNA molecules is crucial for development, differentiation and normal functioning of the cells. The ncRNAs expression patterns can therefore be used as molecular markers for specific diagnostic methods.
Collapse
Affiliation(s)
- Maciej Szymanski
- Institute of Bioorganic Chemistry of the Polish Academy of Sciences, Noskowskiego 12, 61704 Poznan, Poland
| | | | | | | |
Collapse
|
41
|
Loesch DZ, Bui QM, Kelso W, Huggins RM, Slater H, Warne G, Bergman PB, Bergman P, Rodda C, Mitchell RJ, Prior M. Effect of Turner's syndrome and X-linked imprinting on cognitive status: analysis based on pedigree data. Brain Dev 2005; 27:494-503. [PMID: 16198207 DOI: 10.1016/j.braindev.2004.12.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Revised: 12/01/2004] [Accepted: 12/28/2004] [Indexed: 11/24/2022]
Abstract
The effects of a monosomy of either the maternally or paternally derived X chromosome in Turner's syndrome (TS) on general neurocognitive status and some executive abilities were assessed using the maximum likelihood estimators for pedigree data. This method increases the power of analysis by accounting for the effect of background heritable variation on a trait. The sample comprised 42 females with regular non-mosaic X monosomy and their non-affected relatives. Wechsler neurocognitive scores and several executive function tests' scores, including the Behaviour Dyscontrol Scale (BDS-2), the Wisconsin Card Sorting Test (WCST), and the Rey Complex Figure Test (RCFT), were considered in the analysis. Results showed a significant effect of TS on all Wechsler index and subtest scores, with greatest deficits observed in Arithmetic, Block Design, Object Assembly and Picture Arrangement, and on the total BDS, RCFT and WCST scores, regardless of parental origin of the single X-chromosome. Our data also showed a significantly higher effect of a paternally derived X chromosome in diminishing the performance on several Wechsler scores relevant to verbal skills, which might suggest X-linked imprinting loci relevant to these skills. Possible reasons for the inconsistency of the results concerning X-linked imprinting of cognitive loci using TS patients are discussed, and the relevance of pedigree analysis to future studies of this problem is emphasized.
Collapse
Affiliation(s)
- Danuta Z Loesch
- School of Psychological Science, La Trobe University, Melbourne, Victoria 3086, Australia.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Weksberg R, Shuman C, Smith AC. Beckwith-Wiedemann syndrome. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2005; 137C:12-23. [PMID: 16010676 DOI: 10.1002/ajmg.c.30058] [Citation(s) in RCA: 253] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Beckwith-Wiedemann syndrome (BWS) is a clinically heterogeneous overgrowth syndrome associated with an increased risk for embryonal tumor development. BWS provides an ideal model system to study epigenetic mechanisms. This condition is caused by a variety of genetic or epigenetic alterations within two domains of imprinted growth regulatory genes on human chromosome 11p15. Molecular studies of BWS have provided important data with respect to epigenotype/genotype-phenotype correlations; for example, alterations of Domain 1 are associated with the highest risk for tumor development, specifically Wilms' tumor. Further, the elucidation of the molecular basis for monozygotic twinning in BWS defined a critical period for imprint maintenance during pre-implantation embryonic development. In the future, such molecular studies in BWS will permit enhanced medical management and targeted genetic counseling.
Collapse
|
43
|
Dong C, Li WD, Geller F, Lei L, Li D, Gorlova OY, Hebebrand J, Amos CI, Nicholls RD, Price RA. Possible genomic imprinting of three human obesity-related genetic loci. Am J Hum Genet 2005; 76:427-37. [PMID: 15647995 PMCID: PMC1196395 DOI: 10.1086/428438] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2004] [Accepted: 12/28/2004] [Indexed: 11/03/2022] Open
Abstract
To detect potentially imprinted, obesity-related genetic loci, we performed genomewide parent-of-origin linkage analyses under an allele-sharing model for discrete traits and under a family regression model for obesity-related quantitative traits, using a European American sample of 1,297 individuals from 260 families, with 391 microsatellite markers. We also used two smaller, independent samples for replication (a sample of 370 German individuals from 89 families and a sample of 277 African American individuals from 52 families). For discrete-trait analysis, we found evidence for a maternal effect in chromosome region 10p12 across the three samples, with LOD scores of 5.69 (single-point) and 4.52 (multipoint) for the pooled sample. For quantitative-trait analysis, we found the strongest evidence for a maternal effect (single-point LOD of 2.85; multipoint LOD of 4.01 for body mass index [BMI] and 3.69 for waist circumference) in region 12q24 and for a paternal effect (single-point LOD of 4.79; multipoint LOD of 3.72 for BMI) in region 13q32, in the European American sample. The results suggest that parent-of-origin effects, perhaps including genomic imprinting, may play a role in human obesity.
Collapse
Affiliation(s)
- Chuanhui Dong
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Wei-Dong Li
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Frank Geller
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Lei Lei
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Ding Li
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Olga Y. Gorlova
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Johannes Hebebrand
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Christopher I. Amos
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - Robert D. Nicholls
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| | - R. Arlen Price
- Center for Neurobiology and Behavior, Department of Psychiatry, and Department of Genetics, University of Pennsylvania, Philadelphia; Institute of Medical Biometry and Epidemiology and Clinical Research Group, Department of Child and Adolescent Psychiatry, Philipps-University of Marburg, Marburg, Germany; and Department of Epidemiology, The University of Texas M. D. Anderson Cancer Center, Houston
| |
Collapse
|
44
|
Paoloni-Giacobino A, Chaillet JR. Genomic imprinting and assisted reproduction. Reprod Health 2004; 1:6. [PMID: 15507137 PMCID: PMC526765 DOI: 10.1186/1742-4755-1-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2004] [Accepted: 10/26/2004] [Indexed: 11/21/2022] Open
Abstract
Imprinted genes exhibit a parent-of-origin specific pattern of expression. Such genes have been shown to be targets of molecular defects in particular genetic syndromes such as Beckwith-Wiedemann and Angelman syndromes. Recent reports have raised concern about the possibility that assisted reproduction techniques, such as in vitro fertilization or intracytoplasmic sperm injection, might cause genomic imprinting disorders. The number of reported cases of those disorders is still too small to draw firm conclusions and the safety of these widely used assisted reproduction techniques needs to be further evaluated.
Collapse
Affiliation(s)
- Ariane Paoloni-Giacobino
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh, W1007 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, Pennsylvania 15213, USA
| | - J Richard Chaillet
- Department of Molecular Genetics and Biochemistry, University of Pittsburgh, W1007 Biomedical Science Tower, 200 Lothrop Street, Pittsburgh, Pennsylvania 15213, USA
| |
Collapse
|
45
|
Kesler SR, Garrett A, Bender B, Yankowitz J, Zeng SM, Reiss AL. Amygdala and hippocampal volumes in Turner syndrome: a high-resolution MRI study of X-monosomy. Neuropsychologia 2004; 42:1971-8. [PMID: 15381027 PMCID: PMC3051368 DOI: 10.1016/j.neuropsychologia.2004.04.021] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2003] [Revised: 03/12/2004] [Accepted: 04/12/2004] [Indexed: 10/26/2022]
Abstract
Turner syndrome (TS) results from partial or complete X-monosomy and is characterized by deficits in visuospatial functioning as well as social cognition and memory. Neuroimaging studies have demonstrated volumetric differences in the parietal region of females with TS compared to controls. The present study examined amygdala and hippocampus morphology in an attempt to further understand the neural correlates of psychosocial and memory functioning in TS. Thirty females with TS age 7.6-33.3 years (mean = 14.7 +/- 6.4) and 29 age-matched controls (mean age = 14.8 +/- 5.9; range = 6.4-32.7) were scanned using high resolution MRI. Volumetric analyses of the MRI scans included whole brain segmentation and manual delineation of the amygdala and hippocampus. Compared to controls, participants with TS demonstrated significantly larger left amygdala gray matter volumes, irrespective of total cerebral tissue and age. Participants with TS also showed disproportionately reduced right hippocampal volumes, involving both gray and white matter. Amygdala and hippocampal volumes appear to be impacted by X-monosomy. Aberrant morphology in these regions may be related to the social cognition and memory deficits often experienced by individuals with TS. Further investigations of changes in medial temporal morphology associated with TS are warranted.
Collapse
Affiliation(s)
- Shelli R Kesler
- Stanford Psychiatry Neuroimaging Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, 401 Quarry Road, MC5719, Stanford, CA 94305-5719, USA.
| | | | | | | | | | | |
Collapse
|
46
|
Kesler SR, Blasey CM, Brown WE, Yankowitz J, Zeng SM, Bender BG, Reiss AL. Effects of X-monosomy and X-linked imprinting on superior temporal gyrus morphology in Turner syndrome. Biol Psychiatry 2003; 54:636-46. [PMID: 13129659 PMCID: PMC3061621 DOI: 10.1016/s0006-3223(03)00289-0] [Citation(s) in RCA: 85] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
BACKGROUND Turner syndrome (TS) results from complete or partial monosomy X. The cognitive phenotype of TS involves preservation of verbal skills with visuospatial functioning deficits. The superior temporal gyrus (STG), which is involved in language capacities, has not been investigated in TS. METHODS The STG was measured in 30 female subjects (mean age = 14.73 +/- 6.41; range = 7.56-33.30) with TS and 30 age-matched control subjects (mean age = 14.63 +/- 5.90; range = 6.35-32.65) using volumetric magnetic resonance imaging analyses. RESULTS -Right STG, including both gray and white matter volumes, was significantly larger in TS compared with control subjects. Overall left STG volume was not significantly different between groups, although left white matter volume was increased in the TS subjects. The TS subgroup with a maternally derived X chromosome (Xm) demonstrated more aberrant STG volumes compared with subjects with a paternally (Xp) derived X and control subjects. The difference in STG volumes between Xm and control subjects involved both white and gray matter. The Xm subjects differed from Xp subjects only in terms of gray matter. CONCLUSIONS These findings suggest that X-monosomy and X-linked imprinting negatively affect STG development, possibly by disrupting neural pruning mechanisms.
Collapse
Affiliation(s)
- Shelli R Kesler
- Stanford Psychiatry Neuroimaging Laboratory, Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, California 94305-5719, USA
| | | | | | | | | | | | | |
Collapse
|
47
|
Du M, Beatty LG, Zhou W, Lew J, Schoenherr C, Weksberg R, Sadowski PD. Insulator and silencer sequences in the imprinted region of human chromosome 11p15.5. Hum Mol Genet 2003; 12:1927-39. [PMID: 12874112 DOI: 10.1093/hmg/ddg194] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The imprinting of the genes on human chromosome 11p15.5 is thought to be controlled by two imprinting control regions located in two differentially methylated CpG islands upstream of the H19 gene (H19 DMR) and in intron 10 of the KCNQ1 gene (KvDMR). We have examined sequences in the human 11p15.5 genomic imprinted region for the presence of insulators and silencers using a position- and enhancer-dependent stable transfection assay. We have confirmed the existence of insulators in H19 DMR and discovered two novel insulators in the IGF2 gene. We have also found two novel silencer sequences; one is located in KvDMR, a region that is thought to contain the promoter for the KCNQ1OT1 transcript, and another is in the CDKN1C gene. We have demonstrated binding of CTCF protein in vitro to all the insulator and silencer sequences that we have detected. We discuss the differences in the regulation of imprinting controlled by the two imprinting control regions in chromosome 11p.
Collapse
Affiliation(s)
- Minjie Du
- Department of Molecular and Medical Genetics, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | | | | | | | | | | | | |
Collapse
|
48
|
Abstract
In contrast to the biallelic expression of most genes, expression of genes subject to genomic imprinting is monoallelic and based on the sex of the transmitting parent. Possession of only a single active allele can lead to deleterious health consequences in humans. Aberrant expression of imprinted genes, through either genetic or epigenetic alterations, can result in developmental failures, neurodevelopmental and neurobehavioral disorders and cancer. The evolutionary emergence of imprinting occurred in a common ancestor to viviparous mammals after divergence from the egg-laying monotremes. Current evidence indicates that imprinting regulation in metatherian mammals differs from that in eutherian mammals. This suggests that imprinting mechanisms are evolving from those that were established 150 million years ago. Therefore, comparing genomic sequence of imprinted domains from marsupials and eutherians with those of orthologous regions in monotremes offers a potentially powerful bioinformatics approach for identifying novel imprinted genes and their regulatory elements. Such comparative studies will also further our understanding of the molecular evolution and phylogenetic distribution of imprinted genes.
Collapse
Affiliation(s)
- Susan K Murphy
- Department of Radiation Oncology, Duke University Medical Center, Durham, NC 27710, USA
| | | |
Collapse
|
49
|
Goldberg M, Wei M, Yuan L, Murty VV, Tycko B. Biallelic expression of HRAS and MUCDHL in human and mouse. Hum Genet 2003; 112:334-42. [PMID: 12589428 DOI: 10.1007/s00439-003-0907-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2002] [Accepted: 12/13/2002] [Indexed: 12/15/2022]
Abstract
At least eight genes clustered in 1 Mb of DNA on human chromosome (Chr) 11p15.5 are subject to parental imprinting, with monoallelic expression in one or more tissues. Orthologues of these genes show conserved linkage and imprinting on distal Chr 7 of mice. The extended imprinted region has a bipartite structure, with at least two differentially methylated DNA elements (DMRs) controlling the imprinting of two sub-domains. We previously described three biallelically expressed genes ( MRPL23, 2G7 and TNNT3) in 100 kb of DNA immediately downstream of the imprinted H19 gene, suggesting that H19 marks one border of the imprinted region. Here we extend this analysis to two additional downstream genes, HRAS and MUCDHL (mu-protocadherin). We find that these genes are biallelically expressed in multiple fetal and adult tissues, both in humans and in mice. The mouse orthologue of a third gene, DUSP8, located between H19 and MUCDHL, is also expressed biallelically. The DMR immediately upstream of H19 frequently shows a net gain of methylation in Wilms tumors, either via Chr 11p15.5 loss of heterozygosity (LOH) or loss of imprinting (LOI), but changes in methylation in CpG-rich sequences upstream and within the MUCDHL gene are rare in these tumors and do not correlate with LOH or LOI. These findings are further evidence for a border of the imprinted region immediately downstream of H19, and the data allow the construction of an imprinting map that includes more than 20 genes, distributed over 3 Mb of DNA on Chr 11p15.5.
Collapse
MESH Headings
- Alleles
- Animals
- Blotting, Southern
- Cadherin Related Proteins
- Cadherins/genetics
- Chromosomes, Human, Pair 11/genetics
- DNA Methylation
- Gene Expression Regulation
- Genes, ras/genetics
- Genetic Linkage
- Genomic Imprinting
- Humans
- Mice
- Polymorphism, Restriction Fragment Length
- Polymorphism, Single-Stranded Conformational
- Protocadherins
- RNA, Long Noncoding
- RNA, Messenger/analysis
- RNA, Untranslated/genetics
- Reverse Transcriptase Polymerase Chain Reaction
- Sequence Analysis, DNA
- Sulfites/metabolism
Collapse
Affiliation(s)
- Michael Goldberg
- Department of Pediatrics, College of Physicians and Surgeons, Columbia University, 630 West 168th Street, New York, NY 10032, USA
| | | | | | | | | |
Collapse
|
50
|
Absence of Ndn, encoding the Prader-Willi syndrome-deleted gene necdin, results in congenital deficiency of central respiratory drive in neonatal mice. J Neurosci 2003. [PMID: 12629158 DOI: 10.1523/jneurosci.23-05-01569.2003] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
necdin (Ndn) is one of a cluster of genes deleted in the neurodevelopmental disorder Prader-Willi syndrome. necdin is upregulated during neuronal differentiation and is thought to play a role in cell cycle arrest in terminally differentiated neurons. Most necdin-deficient Ndn(tm2Stw) mutant pups carrying a targeted replacement of Ndn with a lacZ reporter gene die in the neonatal period of apparent respiratory insufficiency. We now demonstrate that the defect can be explained by abnormal neuronal activity within the putative respiratory rhythm-generating center, the pre-Bötzinger complex. Specifically, the rhythm is unstable with prolonged periods of depression of respiratory rhythmogenesis. These observations suggest that the developing respiratory center is particularly sensitive to loss of necdin activity and may reflect abnormalities of respiratory rhythm-generating neurons or conditioning neuromodulatory drive. We propose that necdin deficiency may contribute to observed respiratory abnormalities in individuals with Prader-Willi syndrome through a similar suppression of central respiratory drive.
Collapse
|