My work is focused on the study of a form of epigenetic inheritance that occurs in males exposed to social instability stress during adolescence. Previous work in our laboratory has demonstrated that these mice transmit anxiety and sociability defects specifically to their female offspring across at least three generations. The stressed males display a reduction of a miRNA family (miR-34c/449a) in mice sperm. Our group found that members of the same sperm miRNA family are also reduced in humans exposed to early life stressors. In mice, this reduction persists in both early embryos through at least the morula stage and in the sperm of males derived from them. Now, we seek to understand how and why these sperm miRNA changes contribute to transmission of stress phenotypes across generations of females as well as the origin of miRNA change in stressed males.