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Feinberg, J. I.

Publications and source records attributed to Feinberg, J. I..

3 recordsLinked to original sources

Placenta DNA methylation at ZNF300 is associated with fetal sex and placental morphology

Fetal sex-specific differences in placental morphology and physiology have been associated with sexually dimorphic health outcomes. However, the molecular mechanisms underlying these sex differences are not well understood. We performed whole genome bisulfite sequencing in 133 placenta samples and discovered a significant difference in DNA methylation (DNAm) at the ZNF300 gene locus between male and female offspring and replicated this result in 6 independent datasets. Additionally, the sex-specific pattern appears to be placenta-specific, is robust to a wide range of gestational ages and adverse health outcomes and is present in sorted placenta villous cytotrophoblast cells. Integration of DNAm, genetic, and placental morphology data from the same individuals revealed ZNF300 methylation is also associated with placenta area, perimeter, and max diameter, genetic variants on chromosomes 5 and X, and may mediate the effects of genetic variation on placental area.

genomics↗

Cord blood DNA methylome in newborns later diagnosed with autism spectrum disorder reflects early dysregulation of neurodevelopmental and X-linked genes

BackgroundAutism spectrum disorder (ASD) is a neurodevelopmental disorder with complex heritability and higher prevalence in males. Since the neonatal epigenome has the potential to reflect past interactions between genetic and environmental factors during early development, we performed whole-genome bisulfite sequencing of 152 umbilical cord blood samples from the MARBLES and EARLI high-familial risk prospective cohorts to identify an epigenomic signature of ASD at birth. ResultsWe identified differentially-methylated regions (DMRs) stratified by sex that discriminated ASD from control cord blood samples in discovery and replication sets. At a region level, 7 DMRs in males and 31 DMRs in females replicated across two independent groups of subjects, while 537 DMR genes in males and 1762 DMR genes in females replicated by gene association. These DMR genes were significantly enriched for brain and embryonic expression, X chromosome location, and identification in prior epigenetic studies of ASD in post-mortem brain. In males and females, autosomal ASD DMRs were significantly enriched for promoter and bivalent chromatin states across most cell types, while sex differences were observed for X-linked ASD DMRs. Lastly, these DMRs identified in cord blood were significantly enriched for binding sites of methyl-sensitive transcription factors relevant to fetal brain development. ConclusionsAt birth, prior to the diagnosis of ASD, a distinct DNA methylation signature was detected in cord blood over regulatory regions and genes relevant to early fetal neurodevelopment. Differential cord methylation in ASD supports the developmental and sex-biased etiology of ASD, and provides novel insights for early diagnosis and therapy.

genomics↗

A meta-analysis of two high-risk prospective cohort studies reveals autism-specific transcriptional changes to chromatin, autoimmune, and environmental response genes in umbilical cord blood

BackgroundAutism spectrum disorder (ASD) is a neurodevelopmental disorder that affects more than 1% of children in the United States. ASD risk is thought to arise from a combination of genetic and environmental factors, with the perinatal period as a critical window. Understanding early transcriptional changes in ASD would assist in clarifying disease pathogenesis and identifying biomarkers and treatments. However, little is known about umbilical cord blood gene expression profiles in babies later diagnosed with ASD compared to non-typically developing (Non-TD) or neurotypical children.\n\nMethodsGenome-wide transcript levels were measured by Affymetrix Human Gene 2.0 array in RNA from umbilical cord blood samples from both the Markers of Autism Risk in Babies--Learning Early Signs (MARBLES) and the Early Autism Risk Longitudinal Investigation (EARLI) high-risk pregnancy cohorts that enroll younger siblings of a child previously diagnosed with ASD. An algorithm-based diagnosis from 36 month assessments categorized the younger sibling as either ASD, typically developing (TD), or not ASD but non-typically developing (Non-TD). 59 ASD, 92 Non-TD, and 120 TD subjects were included and differences were identified in ASD versus TD subjects, with Non-TD versus TD as a specificity control. Meta-analysis was used to combine the results from both studies. Functional enrichments of differentially-expressed genes were examined across diagnostic groups.\n\nResultsWhile cord blood gene expression differences comparing either ASD or Non-TD to TD did not reach genome-wide significance when adjusting for multiple comparisons, 172 genes were nominally differentially-expressed between ASD and TD cord blood (log2(fold change) > 0.1, p < 0.01). These genes were significantly enriched for toxic substance response and xenobiotic metabolism functions, and gene sets involved in chromatin regulation and systemic lupus erythematosus were significantly upregulated (FDR q < 0.05). In contrast, 66 genes were differentially-expressed between Non-TD and TD cord blood, including only 8 genes that were also differentially-expressed in ASD.\n\nConclusionsThis is the first study to identify perinatal gene expression differences in umbilical cord blood specific to ASD. The results of this meta-analysis across two prospective ASD cohorts support involvement of environmental, immune, and epigenetic mechanisms in ASD etiology.

genomics↗