Table 1.
Epigenome-wide studies and findings
| Study description | Tissue | Participants | Findings | |
|---|---|---|---|---|
| EWAS | ||||
| Ginsberg et al.103 | Genotyping and DNA methylation (DNAm) sequencing | Brain: cerebellar and occipital tissue | 9 ASD individuals and 9 controls | Found no changes in DNA methylation between the groups. Found downregulation of genes of MOP and protein translation |
| Ladd-Acosta et al.48 | DNAm | Brain: DLPC, temporal cortex and cerebellum | 19 autism cases and 21 controls | Found 4 significant DMRs in: TSPAN32, PRRT1, ZFP57, SDHAP3 |
| Nardone et al.49 | DNAm | Brain: nterior cingulate gyrus and prefrontal cortex | ACG: 11 ASD cases and 11 controls | Found 5329 DMPs with significant methylation changes compared to controls. Found brain regions less epigenetically varied than the controls. Implicated genes HDAC4and C11ORF21 |
| PFC: 12 ASD cases and 12 controls | ||||
| Peripheral tissues | ||||
| Nguyen et al.104 | Global methylation profile of LCLs | Lymphoblastoid cell line | 3 pairs of twins discordant in autism | 2 candidate genes, BCL-2 and RORA, exhibited hypermethylation of specific CpG sites (gene silencing) |
| Wang et al.105 | DNAm in PBCs | Blood | 5 ASD children and 5 age/sex-matched controls | Indicated ENO2 to a subset of autism and pointed to as potential biomarker. This association has not been found since |
| Wong et al.50 | Differentially methylated CpG sites of whole blood samples | Blood | 50 pairs of monozygotic twins | Genes found to be differentially methylated: NFYC, DUSP2 |
| Similarities in PXDN and C11ORF1 in at least two discordant twins | ||||
| MDPs in MGC3207, OR2L13, FAM181A | ||||
| Berko et al.51 | DNAm | Buccal epithelium | 47 ASD cases and 48 controls | Found ASD-specific DMRs. A DMR in the OR2L13 gene promoter of the ASD-specific DMP also found in peripheral blood |
| HAWAS | ||||
| Sun et al.106 | Histone acetylation population study | Brain: prefrontal and temporal cortex, cerebellum | 45 ASD samples and 49matched controls | More than 68% of syndromic and idiopathic ASD cases share common acetylome signature in the prefrontal and temporal cortex |
DNAm DNA methylation, MOP mitochondrial oxidative phosphorylation, DLPC dorsolateral prefrontal cortex, DMR differentially methylated region, ACG anterior cingulate gyrus, PFC prefrontal cortex, DMP differential methylated position, LCL B-cell derived lymphoblastoid cell lines, PBC peripheral blood cell, HAWAS histone acetylome-wide association study