The Role of Angiotensin Converting Enzyme 2 in the Gastrointestinal Infection Risk and Potential Fecal Oral-Transmission Route of 2019-nCoV

With the global spread of 2019-nCoV, numerous clinical manifestations and affected organs have been reported. Authors noticed that there were patients with diarrhea symptoms, and other researchers have reported detection of 2019-nCoV in human feces. We carried out PPI analysis on the receptor gene ACE2 by STRING, and studied the tissue specific expression and function of the candidate gene set. Meanwhile, the single-cell database was used to query and analyze the key receptor cells of the virus which invaded into the small intestinal tissues, try to look for the possible molecular mechanisms by which viruses caused diarrhea. We found that 11 closely interacted genes (ACE2, AGT, AGTR1, AGTR2, MME, PRCP, REN, DPP4, MEP1A, MEP1B, XPNPEP2) showed tissue specific aggregation expression in kidney and small intestine (duodenum), suggesting that the ACE2 may have a differential response mechanism in different tissues. Gene function analysis found that the gene clusters with specific aggregation expression in the small intestine tend to accumulate in protein digestion and absorption pathway. By querying in the Mouse Cell Atlas (MCA), we believe that the virus may be using the epithelial cells of small intestine as receptor cells, interfering amino acid transport and causing symptoms such as diarrhea by affecting the protein digestion and absorption pathway. Certainly, diarrhea may also be a symptom of complications caused by other affected organs, and the authors need more clinical information and molecular data for further studies. Funding Statement: None. Declaration of Interests: The authors declare that they have no competing financial interests.