Association between different parameters of child maltreatment and global DNA methylation

Abstract

Exposure to early life adversities, as child maltreatment may disturb the whole biological development of a child resulting in different consequences. Among the main underlying mechanisms are epigenetics and DNA methylation. The aim of the study was to access the effects of various factors such as child maltreatment (single or multiple), duration, frequency and age of onset of abuse on DNA methylation. Subjects and methods: 90 children (55 males, 35 females) aged 12-18 years were recruited from adolescent psychiatric outpatient clinics at Al-Hadara University Hospital in Alexandria, Egypt. A Childhood Trauma Questionnaire was used to take the history of child maltreatment. Global DNA methylation was determined by MethylFlash methylated DNA quantification colorimetric kit. Results: Regarding DNA methylation, there was a statistically significant hypomethylation was detected among those who reported exposure to more than one type of child maltreatment than those who reported no exposure or exposure to only one type. Significant difference was also detected between children who were exposed at the age of nine or less and those above 9 years. Moreover, a significant association was found between the duration and frequency of maltreatment in the prediction of DNA methylation. Conclusion: global DNA hypomethylation can be used as a marker to detect exposure to multiple types of child maltreatment. However, it is not about the early child maltreatment alone, but the accumulation of abuse over time and higher frequency of exposure to child maltreatment that causes more global DNA hypomethylation. ARTICLE HISTORY

Biological embedding of child maltreatment: A systematic review of biomarkers and resilience in children and youth.

“…Highest mean methylation values were measured in children exposed to one CM type or no CM. Children who experienced four types and two types evidenced lower methylation levels, while the lowest levels were found in children who experienced three types of CM (Seif et al, 2019). When CM types were assessed separately, DNAm level was significantly associated with physical abuse only.…”

“…An additional two studies carried out EWAS using a CM measure that included all subtypes except IPV exposure (Cicchetti et al, 2016; Seif et al, 2019). Cicchetti et al (2016) found differences in methylation between maltreated and nonmaltreated children at 1,876 CpG sites with a 6.2% mean difference between groups.…”

“…Further analyses that examined interactions between CM exposure and known disease biomarkers identified differentially methylated sites associated with mental health, cancer, cardiovascular systems, and immune function, suggesting that maltreated children are at greater risk for adverse physical and mental health outcomes associated with these methylation differences (Cicchetti et al, 2016). The second study stratified children by co-occurrence of CM subtypes, dividing groups into no CM, one, two, three, or four CM types, and found statistically significant differences in methylation between all groups (Seif et al, 2019). Highest mean methylation values were measured in children exposed to one CM type or no CM.…”

“…Frequency was significantly and inversely associated with DNAm, with highest mean methylation in participants with 1–2 exposures and lowest methylation in children exposed more than ten times. Using multivariate linear regression to examine interactions between CM, methylation and CM characteristics, a significant association was found between duration and frequency of exposure and DNAm (Seif et al, 2019). Taken together, findings suggest CM is associated with differential methylation, and that experiencing multiple types, more frequent CM, and CM over a longer period may amplify effects.…”

Conducting epigenetics research with refugees and asylum seekers: attending to the ethical challenges

“…Epigenetic studies are engaging with important epidemiological questions regarding the relationship between health and social status, the role of early developmental events on the health of adults, the influence of lifestyles on people’s phenotype later in life, the health effects of exposures to various environmental chemicals, and the impact of these various factors across generations. Epigenetic modifications have been used as biomarkers for life adversity [ 16 ], pregnancy outcomes [ 17 ] and reproductive disease [ 18 ]. Recent epigenetic research has called attention to the ways in which violence can produce epigenetic changes that can affect physical and mental health status and can transcend generations [ 14 ].…”