It is a sexually transmitted disease, though an infant may be infected during birth.

This similarity suggests M. penetrans could attach to host cells through cytadherence.

[5] Mycoplasma penetrans, like many bacteria, exhibits a mechanism by which it can avoid an immune response in the host cells.

In M. penetrans, this promoter region can undergo reversible inversion, allowing for variation in antigen production and, thus, the source for M. penetrans antigenic variation.

[6] Mycoplasma penetrans has been shown to hinder p53, a tumor suppressing gene that aids in regulating the cell cycle.