All research described in this dissertation is focused on understanding the pathophysiology of three rare congenital diseases of the intestine, including megacystis microcolon intestinal hypoperistalsis syndrome (MMIHS), congenital short bowel syndrome (CSBS), and hereditary multiple intestinal atresia (HMIA).

For MMIHS and HMIA, we follow a comparable path, starting a search for the genetic cause of the disease by SNP arrays and exome sequencing. Subsequently, after identifying the candidate genes, we performed both in vitro and in vivo assays to prove causality and to determine the mechanism underlying the disease development. For CSBS, we performed functional work to unravel disease mechanism.