PSEN1 and Alzheimer disease: Therefore, based on our previous results on SAM supplementation to adult TgCRND8 mice, and within the framework of a larger project aimed at exploring the role of PSEN1 methylation and expression during neurodevelopment and neurodegeneration [25], we decided to investigate whether perinatal SAM supplementation could affect PSEN1 expression and AD-like phenotypes in TgCRND8 mice.