@article {558, title = {Whole exome sequencing of Rett syndrome-like patients reveals the mutational diversity of the clinical phenotype.}, journal = {Hum Genet}, volume = {135}, year = {2016}, month = {2016 12}, pages = {1343-1354}, abstract = {

Classical Rett syndrome (RTT) is a neurodevelopmental disorder where most of cases carry MECP2 mutations. Atypical RTT variants involve mutations in CDKL5 and FOXG1. However, a subset of RTT patients remains that do not carry any mutation in the described genes. Whole exome sequencing was carried out in a cohort of 21 female probands with clinical features overlapping with those of RTT, but without mutations in the customarily studied genes. Candidates were functionally validated by assessing the appearance of a neurological phenotype in Caenorhabditis elegans upon disruption of the corresponding ortholog gene. We detected pathogenic variants that accounted for the RTT-like phenotype in 14 (66.6~\%) patients. Five patients were carriers of mutations in genes already known to be associated with other syndromic neurodevelopmental disorders. We determined that the other patients harbored mutations in genes that have not previously been linked to RTT or other neurodevelopmental syndromes, such as the ankyrin repeat containing protein ANKRD31 or the neuronal acetylcholine receptor subunit alpha-5 (CHRNA5). Furthermore, worm assays demonstrated that mutations in the studied candidate genes caused locomotion defects. Our findings indicate that mutations in a variety of genes contribute to the development of RTT-like phenotypes.

}, keywords = {Adolescent, Adult, Animals, Caenorhabditis elegans, Carrier Proteins, Cell Cycle Proteins, Child, Child, Preschool, DNA Mutational Analysis, Exome, Female, Forkhead Transcription Factors, Genetic Variation, High-Throughput Nucleotide Sequencing, Humans, Methyl-CpG-Binding Protein 2, mutation, Nerve Tissue Proteins, Protein Serine-Threonine Kinases, Receptors, Nicotinic, Rett Syndrome}, issn = {1432-1203}, doi = {10.1007/s00439-016-1721-3}, author = {Lucariello, Mario and Vidal, Enrique and Vidal, Silvia and Saez, Mauricio and Roa, Laura and Huertas, Dori and Pineda, Merc{\`e} and Dalf{\'o}, Esther and Dopazo, Joaquin and Jurado, Paola and Armstrong, Judith and Esteller, Manel} } @article {1074, title = {A Comprehensive DNA Methylation Profile of Epithelial-to-Mesenchymal Transition.}, journal = {Cancer research}, volume = {74}, number = {19}, year = {2014}, month = {2014 Aug 8}, pages = {5608{\textendash}19}, abstract = {Epithelial-to-mesenchymal transition (EMT) is a plastic process in which fully differentiated epithelial cells are converted into poorly differentiated, migratory and invasive mesenchymal cells and it has been related to the metastasis potential of tumors. This is a reversible process and cells can also eventually undergo mesenchymal-to-epithelial transition (MET). The existence of a dynamic EMT process suggests the involvement of epigenetic shifts in the phenotype. Herein, we obtained the DNA methylomes at single-base resolution of MDCK cells undergoing epithelial-to-mesenchymal transition (EMT) and translated the identified differentially methylated regions (DMRs) to human breast cancer cells undergoing a gain of migratory and invasive capabilities associated with the EMT phenotype. We noticed dynamic and reversible changes of DNA methylation, both on promoter sequences and gene-bodies in association with transcription regulation of EMT-related genes. Most importantly, the identified DNA methylation markers of EMT were present in primary mammary tumors in association with the epithelial or the mesenchymal phenotype of the studied breast cancer samples.}, keywords = {Methyl-Seq, Methylomics, Next Generation Sequencing}, issn = {1538-7445}, doi = {10.1158/0008-5472.CAN-13-3659}, url = {http://www.ncbi.nlm.nih.gov/pubmed/25106427}, author = {Carmona, F Javier and Davalos, Veronica and Vidal, Enrique and Gomez, Antonio and Heyn, Holger and Hashimoto, Yutaka and Vizoso, Miguel and Martinez-Cardus, Anna and Sayols, Sergi and Ferreira, Humberto and Sanchez-Mut, Jose and Moran, Sebastian and Margeli, Mireia and Castella, Eva and Berdasco, Maria and Stefansson, Olafur Andri and Eyfjord, Jorunn E and Gonzalez-Suarez, Eva and Dopazo, Joaquin and Orozco, Modesto and Gut, Ivo and Esteller, Manel} } @article {524, title = {Whole-genome bisulfite DNA sequencing of a DNMT3B mutant patient.}, journal = {Epigenetics}, volume = {7}, year = {2012}, month = {2012 Jun 01}, pages = {542-50}, abstract = {

The immunodeficiency, centromere instability and facial anomalies (ICF) syndrome is associated to mutations of the DNA methyl-transferase DNMT3B, resulting in a reduction of enzyme activity. Aberrant expression of immune system genes and hypomethylation of pericentromeric regions accompanied by chromosomal instability were determined as alterations driving the disease phenotype. However, so far only technologies capable to analyze single loci were applied to determine epigenetic alterations in ICF patients. In the current study, we performed whole-genome bisulphite sequencing to assess alteration in DNA methylation at base pair resolution. Genome-wide we detected a decrease of methylation level of 42\%, with the most profound changes occurring in inactive heterochromatic regions, satellite repeats and transposons. Interestingly, transcriptional active loci and ribosomal RNA repeats escaped global hypomethylation. Despite a genome-wide loss of DNA methylation the epigenetic landscape and crucial regulatory structures were conserved. Remarkably, we revealed a mislocated activity of mutant DNMT3B to H3K4me1 loci resulting in hypermethylation of active promoters. Functionally, we could associate alterations in promoter methylation with the ICF syndrome immunodeficient phenotype by detecting changes in genes related to the B-cell receptor mediated maturation pathway.

}, keywords = {B-Lymphocytes, Cell Line, Transformed, Child, Preschool, DNA (Cytosine-5-)-Methyltransferases, DNA Methylation, Epigenesis, Genetic, Face, Female, Genome, Human, High-Throughput Nucleotide Sequencing, Humans, Immunologic Deficiency Syndromes, mutation, Primary Immunodeficiency Diseases, Sequence Analysis, DNA, Sulfites}, issn = {1559-2308}, doi = {10.4161/epi.20523}, author = {Heyn, Holger and Vidal, Enrique and Sayols, Sergi and Sanchez-Mut, Jose V and Moran, Sebastian and Medina, Ignacio and Sandoval, Juan and Sim{\'o}-Riudalbas, Laia and Szczesna, Karolina and Huertas, Dori and Gatto, Sole and Matarazzo, Maria R and Dopazo, Joaquin and Esteller, Manel} } @article {20028698, title = {Changes in the pattern of DNA methylation associate with twin discordance in systemic lupus erythematosus.}, journal = {Genome research}, volume = {20}, year = {2010}, month = {2010 Feb}, pages = {170-9}, abstract = {

Monozygotic (MZ) twins are partially concordant for most complex diseases, including autoimmune disorders. Whereas phenotypic concordance can be used to study heritability, discordance suggests the role of non-genetic factors. In autoimmune diseases, environmentally driven epigenetic changes are thought to contribute to their etiology. Here we report the first high-throughput and candidate sequence analyses of DNA methylation to investigate discordance for autoimmune disease in twins. We used a cohort of MZ twins discordant for three diseases whose clinical signs often overlap: systemic lupus erythematosus (SLE), rheumatoid arthritis, and dermatomyositis. Only MZ twins discordant for SLE featured widespread changes in the DNA methylation status of a significant number of genes. Gene ontology analysis revealed enrichment in categories associated with immune function. Individual analysis confirmed the existence of DNA methylation and expression changes in genes relevant to SLE pathogenesis. These changes occurred in parallel with a global decrease in the 5-methylcytosine content that was concomitantly accompanied with changes in DNA methylation and expression levels of ribosomal RNA genes, although no changes in repetitive sequences were found. Our findings not only identify potentially relevant DNA methylation markers for the clinical characterization of SLE patients but also support the notion that epigenetic changes may be critical in the clinical manifestations of autoimmune disease.

}, author = {Javierre, Biola M and Fernandez, Agustin F and Richter, Julia and Fatima Al-Shahrour and Martin-Subero, J Ignacio and Rodriguez-Ubreva, Javier and Berdasco, Maria and Fraga, Mario F and O{\textquoteright}Hanlon, Terrance P and Rider, Lisa G and Jacinto, Filipe V and Lopez-Longo, F Javier and Dopazo, Joaquin and Forn, Marta and Peinado, Miguel A and Carre{\~n}o, Luis and Sawalha, Amr H and Harley, John B and Siebert, Reiner and Esteller, Manel and Miller, Frederick W and Ballestar, Esteban} }