Leukocyte Methylomic Imprints of Exposure to the Genocide against the Tutsi in Rwanda: a Pilot Epigenome-Wide Analysis

Abstract

<b>Aim & methods:</b> We conducted a pilot epigenome-wide association study of women from Tutsi ethnicity exposed to the genocide while pregnant and their resulting offspring, and a comparison group of women who were pregnant at the time of the genocide but living outside of Rwanda.<b>Results:</b> Fifty-nine leukocyte-derived DNA samples survived quality control: 33 mothers (20 exposed, 13 unexposed) and 26 offspring (16 exposed, 10 unexposed). Twenty-four significant differentially methylated regions (DMRs) were identified in mothers and 16 in children. <b>Conclusions:</b><i>In utero</i> genocide exposure was associated with CpGs in three of the 24 DMRs: <i>BCOR</i>, <i>PRDM8</i> and <i>VWDE</i>, with higher DNA methylation in exposed versus unexposed offspring. Of note, <i>BCOR</i> and <i>VWDE</i> show significant correlation between brain and blood DNA methylation within individuals, suggesting these peripherally derived signals of genocide exposure may have relevance to the brain.