How Much Junk Is in Your DNA Trunk? [Science Video] The human genome is 3.2 billion base pairs long and contains around 20,000 genes, but how much of that is garbage? Find out in this episode of SciShow! [SciShow] Sharing is Caring:FacebookTwitterEmailMorePinterestMastodon Geeks are Sexy needs YOUR help. Learn more about how YOU can support us here.