The H. pylori PAI was initially called cag cytotoxin associated gene because it was thought to be associated with the expression of VacA vacuolating cytotoxin. However, it was subsequently observed that VacA and PAI are independent 4, 8.
PAI de H. pylori inicialmente se denominó cag gen asociado a citotoxina ya que se pensaba que estaba asociado con la expresión de VacA vacuolotoxina; sin embargo, posteriormente se observó que los dos factores VacA y PAI son independientes 4, 8.