At school, we've been taught that human infants produce rennin/chymosin (which aids in the digestion of milk). More specifically, it is the peptic cells in the stomach which secrete prorennin, the inactive form of rennin (in addition to pepsinogen, the pepsin proenzyme).
User @another'homosapien's answer here also seems to concur with this (excellent answer by the way, I enjoyed reading it).
According to Mod. @AliceD's answer here (yet another excellent answer):
...in humans there is only a chymosin pseudogene present...
Which (probably?) implies that humans (infant or otherwise) do not produce rennin.
I managed to get my hands on the Textbook of Medical Physiology (Guyton and Hall, South-Asian edition), and according to the book (Chapter Gastric secretions, page 406) peptic cells produce a large quantity of pepsinogen. There is, however, no mention of prorennin. I even flipped over to the Appendix at the back to look up "Rennin", but it turns out there is absolutely no mention of rennin in the book.
Some sources claim that rennin is produced in human (infants). Is this true?
Other sources claim that rennin is not produced in humans ( we have a pseudogene for it though). Is this correct (I mean the "rennin-is-not-produced" bit, not the "pseudogene" bit)?
If rennin is produced in humans only during infancy, what stops it from being produced as we mature? (I'm asking this because every source I've seen that claims that rennin is produced in humans, explicitly states that is done so during infancy...which would suggest that rennin is not produced in adults)