Following transfection, X can be either transiently expressed in {HEAD ~ undifferentiated cells} in {TAIL ~ the population}, or P X can be inheritable and expressed in undifferentiated progeny 
in
Following transfection , X can be either transiently expressed in { HEAD ~ undifferentiated cells } in { TAIL ~ the population } , or P X can be inheritable and expressed in undifferentiated progeny
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH