Patients with autism spectrum disorder (ASD) are often accompanied by inflammatory bowel disease (IBD) in observational research; however, the potential causal link between the two conditions remains unknown. In this study, we used a two-sample bidirectional Mendelian randomization (MR) approach to assess the causal relationship between ASD and IBD and its main subtypes, Crohn's disease (CD), and ulcerative colitis (UC). Independent genetic instruments from a genome-wide association study (GWAS) for IBD (25,042 cases and 34,915 controls) were u...
