As mentioned above, bi-allelic LOF variants in TGFB1 were recently identified in 3 patients from 2 unrelated families presenting with severe very early onset IBD, manifesting as bloody diarrhea with failure to thrive, and central nervous system (CNS) disease associated with epilepsy, brain atrophy and posterior leukoencephalopathy (2). This evidence concerns the gene TGFB1 and inflammatory bowel disease.