Wood, N..1, Trebilco, T.1, & Cohen-Woods, S.1
1 College of Education, Psychology & Social Work, Flinders University
Childhood socioeconomic position (SEP) has potential to alter epigenetic pathways associated in the development of adulthood psychiatric outcomes. We present a systematic review synthesising the literature investigating childhood SEP and DNA methylation, with a focus on pathways involved in the development of psychiatric outcomes. We reviewed literature up to October 2019 from three databases. Studies investigating childhood SEP and DNA methylation were identified, resulting in inclusion of thirty-two publications. In total seventeen studies focused on candidate genes, typically focusing on genes implicated with the stress response and/or development of psychiatric conditions. There was little overlap of genes studied, with three genes were studied more than once. These studies typically investigated different regions of the genes, which revealed inconsistent results. Six studies calculated epigenetic age, with a small number revealing a significant association with childhood SEP. Epigenome-wide studies revealed altered patterns of DNA methylation, but patterns varied between the nine studies. This research area is emerging, and no clear patterns identified across studies. It is critical to consider factors that contribute to these variances to inform research practice, and long-term uncover replicable findings. Multiple methodological shortcomings are identified, including at the phenotypic level where construct validity of childhood SEP is highly problematic, with studies using a wide range of measures. At the epigenomic and epigenetic level studies fail to consistently use suitable controls. Study designs often utilised small samples sizes, and no pre-registered studies are reported. Larger cohorts will be required with international collaborations to strengthen this research area.
Natasha is a PhD candidate (Clinical Psychology) in the Behavioural Genomic and Environmental Mechanisms Lab at Flinders University. Natasha completed her Bachelor of Psychology (First Class Honours) in 2016 and commenced her Clinical PhD in 2018. Her research focuses on investigating the association between social disadvantage, genomic outcomes, and child and adult behaviour. Natasha is also undertaking clinician training at Flinders University and develops her clinical skills through placements and skill-based assessments. She is currently on placement as a Provisional Psychologist at Older Persons Mental Health Service in the Eastern Community team (Central Adelaide Local Health Network) and will be undertaking her next placement at the Central Australian Aboriginal Congress in Alice Springs in the latter half of 2020.