16p11.2 microdeletions are genetically associated with autism spectrum disorder (ASD), but the links to the various patient phenotypes are not well understood. In a new paper in Development, Rana Fetit and colleagues use ventral organoids derived from induced pluripotent stem cells to dissect the effect of 16p11.2 microdeletions on interneuron development. We caught up with corresponding author Rana Fetit and group leader David Price to find out more about their research.