Mutations in MECP2, encoding methyl CpG binding protein 2 (MeCP2), cause most cases of Rett syndrome (RTT), an X-linked neurodevelopmental disorder. Both RTT and autism are "pervasive developmental disorders" and share a loss of social, cognitive and language skills and a gain in repetitive stereotyped behavior, following apparently normal perinatal development. Although MECP2 coding mutations are a rare cause of autism, MeCP2 expression defects were previously found in autism brain. To further study the role of MeCP2 in autism spectrum disorders (ASDs), we determined the frequency of MeCP2 expression defects in brain samples from autism and other ASDs. We also tested the hypotheses that MECP2 promoter mutations or aberrant promoter methylation correlate with reduced expression in cases of idiopathic autism. MeCP2 immunofluorescence in autism and other neurodevelopmental disorders was quantified by laser scanning cytometry and compared with control postmortem cerebral cortex samples on a large tissue microarray. A significant reduction in MeCP2 expression compared to age-matched controls was found in 11/14 autism (79%), 9/9 RTT (100%), 4/4 Angelman syndrome (100%), 3/4 Prader-Willi syndrome (75%), 3/5 Down syndrome (60%), and 2/2 attention deficit hyperactivity disorder (100%) frontal cortex samples. One autism female was heterozygous for a rare MECP2 promoter variant that correlated with reduced MeCP2 expression. A more frequent occurrence was significantly increased MECP2 promoter methylation in autism male frontal cortex compared to controls. Furthermore, percent promoter methylation of MECP2 significantly correlated with reduced MeCP2 protein expression. These results suggest that both genetic and epigenetic defects lead to reduced MeCP2 expression and may be important in the complex etiology of autism.

The function of the lung is dependent upon differentiation and proliferation of respiratory epithelial cells and the synthesis/secretion of surfactant lipids and proteins into air space. During the respiratory inflammatory response, cytokines produced by macrophages and epithelial cells in the respiratory system have significant influence on surfactant protein homeostasis. We report here that among family members of Janus family tyrosine kinase (JAK) and signal transducers and activators of transcription (STAT), only JAK 1 and STAT3 stimulated the ؊500 to ؉41 promoter activity of the surfactant protein B (SP-B) gene in respiratory epithelial cells. JAK1 and STAT3 were co-localized in alveolar type II epithelial cells where SP-B is synthesized and secreted. Interleukin 6 and interleukin 11, known to activate STAT3 synergistically, stimulated the SP-B promoter activity with retinoic acid, which is at least partially mediated through interactions between STAT3 and retinoid nuclear receptor enhanceosome proteins in pulmonary epithelial cells.The lung has the largest epithelial surface area of the body in order to facilitate air exchange. The structure of alveoli is protected by surfactant membrane. Pulmonary surfactant is a complex mixture of lipids and proteins that form an insoluble film to reduce surface tension at the air/liquid interface in the alveoli. The reduction of surface tension at the alveolar surface promotes lung expansion on inspiration and prevents lung collapse on expiration. Deficiency of pulmonary surfactant is responsible for increased surface tension along the alveolar epithelium and brings about alveolar collapse and epithelial cell lysis, resulting in respiratory distress syndrome, a major cause of morbidity and mortality in preterm infants. Pulmonary surfactant is composed of 90 -95% lipids and 5-10% proteins. Among surfactant proteins, SP-B 1 is a 79-amino acid amphipathic peptide produced by the proteolytic cleavage of proSP-B in alveolar type II and Clara epithelial cells. The SP-B peptide is stored in lamellar bodies and secreted with phospholipids into the airway lumen. It facilitates the stability and rapid spreading of surfactant phospholipids during respiratory cycles (1). SP-B plays a critical role in postnatal lung function.

Epigenetic mechanisms have been proposed to play a role in the etiology of autism. This hypothesis is supported by the discovery of increased MECP2 promoter methylation associated with decreased MeCP2 protein expression in autism male brain. To further understand the influence of female X chromosome inactivation (XCI) and neighboring methylation patterns on aberrant MECP2 promoter methylation in autism, multiple methylation analyses were peformed on brain and blood samples from individuals with autism. Bisulfite sequencing analyses of a region 0.6 kb upstream of MECP2 in brain DNA samples revealed an abrupt transition from a highly methylated region in both sexes to a region unmethylated in males and subject to XCI in females. Chromatin immunoprecipitation analysis demonstrated that the CCTC-binding factor (CTCF) bound to this transition region in neuronal cells, consistent with a chromatin boundary at the methylation transition. Male autism brain DNA samples displayed a slight increase in methylation in this transition region, suggesting a possible aberrant spreading of methylation into the MECP2 promoter in autism males across this boundary element. In addition, autistic female brain DNA samples showed evidence for aberrant MECP2 promoter methylation as an increase in the number of bisulfite sequenced clones with undefined XCI status for MECP2 but not androgen receptor (AR). To further investigate the specificity of MECP2 methylation alterations in autism, blood DNA samples from females and mothers of males with autism were also examined for XCI skewing at AR, but no significant increase in XCI skewing was observed compared to controls. These results suggest that the aberrant MECP2 methylation in autism brain DNA samples is due to locus-specific rather than global X chromosome methylation changes.

Primary biliary cirrhosis (PBC) is an uncommon autoimmune disease with a homogeneous clinical phenotype that reflects incomplete disease concordance in monozygotic (MZ) twins. We have taken advantage of a unique collection consisting of genomic DNA and mRNA from peripheral blood cells of female MZ twins (n = 3 sets) and sisters of similar age (n = 8 pairs) discordant for disease. We performed a genome-wide study to investigate differences in (i) DNA methylation (using a custom tiled four-plex array containing tiled 50-mers 19,084 randomly chosen methylation sites), (ii) copy number variation (CNV) (with a chip including markers derived from the 1000 Genomes Project, all three HapMap phases, and recently published studies), and/or (iii) gene expression (by whole-genome expression arrays). Based on the results obtained from these three approaches we utilized quantitative PCR to compare the expression of candidate genes. Importantly, our data support consistent differences in discordant twins and siblings for the (i) methylation profiles of 60 gene regions, (ii) CNV of 10 genes, and (iii) the expression of 2 interferon-dependent genes. Quantitative PCR analysis showed that 17 of these genes are differentially expressed in discordant sibling pairs. In conclusion, we report that MZ twins and sisters discordant for PBC manifest particular epigenetic differences and highlight the value of the epigenetic study of twins.

A corrigendum on Genome-wide analysis of DNA methylation, copy number variation, and gene expression in monozygotic twins discordant for primary biliary cirrhosis

Background Cardiac rhythm devices (CRD) require complex management to identify potential device or patient issues. While easy to obtain, report processing is complex and time consuming. In our population, a majority of reports were performed outside of institutional protocols and no method for electrophysiology (EP) notification for unscheduled reports existed. These process breakdowns led to potential issues with safety and associated loss of work efficiency. Objective Our aim was to decrease the percentage of reports without EP notification from 30% to 10% over a 9-month time period. Methods We created a detailed process map of in-office and home device reporting. Failure mode and effects analysis (FMEA)/Pareto charts were used to determine the mechanistic underpinnings of notification failures and identify areas for process improvement. Multiple interventions were implemented using the Plan-Do-Study-Act (PDSA) technique. Process run charts and control charts were used to evaluate ongoing changes. Results Our FMEA identified failures related to (1) lack of physician understanding of the device reporting system, (2) lack of an easy to use method of EP notification and (3) lack of patient understanding of report notification. Pareto charts identified the most frequent failures to be associated with specific cardiology subspecialties as well as reports sent from home. We performed multiple interventions including(1) creation of an easy to use method of EP notification used by patients and medical staff, (2) physician education and (3) patient education. Compared with baseline reporting, there was a decrease from 30% to <10% of device reports obtained without EP notification. This process improvement additionally resulted in a 34% reduction in time required for device processing. Conclusions Development of a unified EP reporting system and quality improvement methodology resulted in improved CRD report notification and improved efficiency for staff. These process changes resulted in improvement across differing cardiac subspecialty providers and patients.

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