Mutations in the proenteropeptidase gene are the molecular cause of congenital enteropeptidase deficiency.
Holzinger A, Maier EM, Bück C, Mayerhofer PU, Kappler M, Haworth JC, Moroz SP, Hadorn HB, Sadler JE, Roscher AA. Am J Hum Genet. 2002 Jan; 70(1):20-5. Epub 2001 Nov 21.