The putatively functional Mkrn1-p1 pseudogene is neither expressed nor imprinted, nor does it regulate its source gene in trans.

A recently promoted genome evolution model posits that mammalian pseudogenes can regulate their founding source genes, and it thereby ascribes an important function to "junk DNA." This model arose from analysis of a serendipitous mouse mutant in which a transgene insertion/deletion caused severe polycystic kidney disease and osteogenesis imperfecta with approximately 80% perinatal lethality, when inherited paternally [Hirotsune, S., et al.