One week after he was born, KJ Muldoon was diagnosed with what doctors call a CPS-1 deficiency, essentially meaning he was missing a critical liver enzyme. With doctors believing they only had six months to come up with a solution, KJ became the first patient in the world to receive a custom gene-editing drug in February — and he is thriving after three doses of the therapy. NBC’s Erin McLaughlin reports for TODAY on how this could be a blueprint for future treatment. » Subscribe to TODAY: youtube.com/@TODAY About: TODAY brings you the latest headlines and expert tips on money, health and parenting. We wake up every morning to give you and your family all you need to start your day. If it matters to you, it matters to us. We are in the people business. Subscribe to our channel for exclusive TODAY archival footage & our original web series. Connect with TODAY Online! Visit TODAY's Website: today.com Find TODAY on Facebook: facebook.com/today Follo...