Synthetic Lethality (cancer terminology that appears in CDK2 context)

**What it means:** Synthetic lethality occurs when a cell survives with just ONE gene broken but dies if a SECOND gene is also broken. Cancer drugs exploit this by killing cancer cells (which already have one broken gene) while leaving normal cells (with both genes intact) alone. **CDK2 and synthetic lethality:** Some cancer cells are "addicted" to CDK2 because they've lost another cell cycle control mechanism. CDK2 inhibitors kill these cells selectively. While MHS doesn't involve cancer, understanding this concept helps explain why CDK2 is such a promising drug target — it's not just about blocking one protein, it's about exploiting a specific vulnerability in cells where the MEF2C-p21-CDK2 pathway is disrupted.