The UK Biobank's imaging study has scanned the brains and bodies of more than 40,000 participants using magnetic resonance imaging (MRI), making it the world's largest multi-modal imaging database. Meanwhile, several independent studies have also produced publicly available imaging genetic datasets. We integrate, process, and use MRI data from over 50,000 subjects to examine the genetic architecture of the human brain and body. In this talk, I will present new findings on the genetic influences of human brain white matter and its genetic links to a wide range of clinical outcomes, including glioma and stroke. Further, I will discuss the statistical issues we encountered when analyzing these datasets and the possible directions for future multi-organ imaging research. This presentation is based on a series of joint works with Hongtu Zhu and the BIG-S2 lab at the University of North Carolina at Chapel Hill. More information about our studies is available at the Brain Imaging Genetics Knowledge Portal (BIG-KP, https://bigkp.org).