Table 1.
A description of the 19 datasets included in this review, summarizing the type of study, the cohort size, the tissue type, and the definition of the final dataset used from each study. DE = differentially expressed; DM = differentially methylated.
| Proteomics Analysis | ||||
|---|---|---|---|---|
| Shen et al., 2019 [11] | 41 DE proteins in ASD | 24 male and 6 female ASD (2–6 yrs) and age/gender-matched controls | Blood | Blood PBMCs |
| Hewitson et al., 2021 [14] | 86 downregulated, 52 upregulated proteins in ASD (FDR < 0.05) | 76 ASD (boys) and 78 controls (boys), 18 months to 8 yrs | Blood serum | |
| Shen et al., 2018 [15] | 24 DE proteins in ASD | 24 male and 6 female autistic patients (2–6 yrs) and age/gender-matched controls | Blood plasma | |
| Yang et al., 2018 [16] | Eight biomarker peaks with higher expression in ASD | Han Chinese children: 68 ASD (average age = 12.4 yrs) and 80 age-matched controls (average age 14.3 yrs) | Blood serum | |
| Yao et al., 2021 [17] | 59 genes predicted to encode ASD-related blood-secretory proteins; six proteins were validated using an ELISA | 79 brain tissue samples from 19 ASD and 17 controls; ELISA analysis of 20 ASD, and 20 age/gender-matched controls. The average age of the patients and controls were 24 yrs (ranged from 2 to 56) and 34.6 yrs (ranged from 16 to 56) respectively | Brain tissue | Blood samples |
| Abraham et al., 2019 [18] | 146 DE proteins from BA19 between ASD and controls (p < 0.05) | 9 ASD cases (2–60 yrs) and 9 age- and gender-matched controls (1–60 yrs) | Cerebellum (CB) and Brodmann area 19 (BA19) | |
| Transcriptomic Meta-Analysis | ||||
| Reference | Dataset Used in Analysis | Cohort | Tissue | |
| Tylee et al., 2017 [19] | 90 DE genes in ASD (p < 0.05) | 626 ASD and 447 controls across seven independent studies; mean age and SD of 5 ± 3.8 yrs | Blood | Ex vivo peripheral blood samples or isolated leukocyte samples derived from peripheral blood |
| Mordaunt et al., 2019 [20] | 172 DE genes in ASD (p < 0.01) | 59 ASD, 92 non-typically developing, 120 typically developing controls | 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 | |
| Gao et al., 2020 [21] | 3624 DE genes in ASD | 96 ASD and 42 controls age range: 2–18 yrs | Peripheral blood samples (GSE18123 and GSE6575) | |
| He et al., 2019 [22] | DE genes (p < 0.05) in ASD | 485 ASD and 398 controls | Five data sets from blood lymphoblastoid cell lines (LCLs) (GSE18123, GSE25507, GSE29691, GSE37772, GSE42133) | |
| He et al., 2019 [22] | DE genes (p < 0.05) in ASD | 109 ASD and 129 controls | Brain tissue | Three data sets from postmortem brain tissue (GSE28475, GSE28521, GSE38322) |
| Forés-Martos et al., 2019 [23] | 1055 DE genes in ASD (FDR p < 0.05) | 34 ASD cases and 130 controls across three studies. Mean age 20.3 yrs | Frontal cortex tissue | |
| Rahman et al., 2020 [24] | 1567 DE genes in ASD | 15 ASD and 15 controls across two studies | Post-mortem brain tissue (GSE30573 and GSE64018) | |
| Wright et al., 2017 [25] | 1463 DE genes in ASD across all moderately expressed Ensembl genes (13,011) at marginal statistical (p < 0.05) significance | 13 ASD (3F, 10M), average age 22 yrs (4 to 67) and 39 controls (9F, 30M), average age 22 yrs (2 to 69) | Postmortem brain tissue: dorsolateral prefrontal cortex | |
| Yao et al., 2021 [17] | 364 DE genes in ASD | 79 brain tissue samples from 19 ASD and 17 controls. Average age of the patients and controls were 24 yrs (2 to 56) and 34.6 yrs (16 to 56) respectively | Brain tissue: cerebellum, frontal cortex, and temporal cortex (GSE28521) | |
| Ramaswami et al., 2020 [26] | 5200 DE genes (FDR < 0.05) | 82 ASD samples and 74 control samples from 47 ASD and 44 control brains from (Parikshak et al.); mean age and SD were 28 (+/−17) yrs | Frontal and temporal cortex tissue from the Harvard Autism Tissue Program and NIH Neuro Brain Bank | |
| DNA Methylation Analysis | ||||
| Mordaunt et al., 2020 [27] | 537 DM genes in both discovery and replication sets in males | Discovery set = 74 males (35 ASD and 39 controls) and 32 females (15 ASD and 17 controls) in the MARBLES and EARLI studies. Replication set = 38 males (21 ASD and 17 controls) and 8 females (5 ASD and 3 controls) | Blood | Umbilical cord blood samples |
| Hu et al., 2020 [28] | 181 DM genes that overlap between the discovery and validation groups MALES | 21 ASD and 21 controls, average age 8.4 yrs | LCLs | |
| Wong et al., 2019 [29] | i)Top ranked iASD-associated DM probes identified in the cross-cortex model incorporating both prefrontal cortex and temporal cortex data | 43 ASD and 38 controls, average age at death 29.0 (+/−18.9) and 48.7 (+/−8.8) yrs respectively | Brain tissue | Post-mortem brain tissue from prefrontal cortex, temporal cortex and cerebellum |
| Ramaswami et al., 2020 [26] | DM genes (promoter or gene body; FDR < 0.05) | 56 ASD samples and 41 control samples from 33 ASD and 26 control brains. Mean age and SD = 34 (+/−15) yrs | Frontal and temporal cortex tissue from the Harvard Autism Tissue Program and NIH Neuro Brain Bank | |
| Stathopoulous et al., 2020 [30] | 898 DM genes in ASD | 48 boys (32 ASD and 16 controls, 6–12 yrs) | Buccal cells | Buccal DNA |