Genes, Gender, and Growing Old

🧬 Your mother's X chromosome may shape how your brain ages. In female mice, when only the maternal X chromosome (Xm) is active, older animals show worse memory 🧠🕳️ than those with random X-inactivation. This is due to imprinted genes — some only expressed from the paternal X (Xp) — which are silent when Xm dominates.   🧠💡 Using CRISPR–Cas9, researchers reactivated 3 Xm-silent genes (Sash3, Tlr7, Cysltr1) and saw improved memory and mitochondrial function ⚡🔋.   👩‍🔬 This highlights inter-female variation in aging and memory — and suggests that epigenetic inheritance from mothers may shape how well we remember… or forget. 🧓🧠❓