 Hashat audio presents inheritance how our genes change our lives how our lives change our genes written and read by Sharon Moalem MD PhD with Matthew D. Le plant for Shira introduction everything is about to change remember the seventh grade can you recall the faces of your fellow students can you summon the names of the teachers the secretary the principal can you hear the way the bell sounded how about the smell of the cafeteria on sloppy Joe day the ache of your first crush panic a finding yourself in the bathroom at the same time as a school bully maybe it's all strikingly clear or maybe over time your middle school years have been lost in the fog of so many other childhood memories either way you're carrying it all with you for a long time now we've understood that we shoulder our experiences in the knapsack of our psyche even things you cannot consciously recall or somewhere in there swimming around in your subliminal mind ready to emerge unexpectedly for good or ill but it's all much deeper than that because your body's in a constant state of transformation and regeneration and your experiences no matter how seemingly inconsequential from bullies to crushes to sloppy Joe's have all left an indelible mark within you and more importantly within your genome of course this isn't how most of us have been taught to think about the three billion letter equation that makes up a genetic inheritance ever since Gregor Mendel's mid 19th century investigations is the heritage traits of P plants were used to set the foundations for our understanding of genetics we've been taught that who we are is a resolutely predictable matter of the genes we've inherited from previous generations a little from mom a little from dad whip it up and there's you that calcified view of genetic inheritance is what students in middle school classrooms are still studying to this day when they map out pedigree charts in an effort to make sense of their fellow students eye color curly hair tongue rolling or hairy fingers and the lesson delivered as though on stone tablets from Mendel himself is that we don't have much of a choice in the matter of what we get or what we give because our genetic legacy was completely fixed when our parents conceived us but that's all wrong because right now whether you're seated at your desk sipping a coffee slumped into a recliner at home riding a stationary bike at the gym or orbiting the planet on the international space station your DNA is being constantly modified like thousands upon thousands of light switches some are turning on while others are turning off all in response to what you're doing and what you're seeing and what you're feeling this process is mediated and orchestrated by how you live where you live the sample complete ready to continue