yme ▁gene ▁ther apy ▁has ▁been ▁the ▁in hib ition ▁of ▁R NA - based ▁vir uses . ▁ ▁A ▁type ▁of ▁synth etic ▁rib oz yme ▁directed ▁against ▁H IV ▁R NA ▁called ▁gene ▁she ars ▁has ▁been ▁developed ▁and ▁has ▁entered ▁clin ical ▁testing ▁for ▁H IV ▁in fection . ▁ ▁Similarly , ▁rib oz ym es ▁have ▁been ▁designed ▁to ▁ ▁target ▁the ▁he pat itis ▁C ▁virus ▁R NA , ▁S AR S ▁coron av irus ▁( S AR S - Co V ), ▁A den ov irus ▁and ▁influen za ▁A ▁and ▁B ▁virus ▁R NA . ▁ ▁The ▁rib oz yme ▁is ▁able ▁to ▁cle ave ▁the ▁conser ved ▁regions ▁of ▁the ▁virus ’ s ▁gen ome ▁which ▁has ▁been ▁shown ▁to ▁reduce ▁the ▁virus ▁in ▁m amm al ian ▁cell ▁culture . ▁ ▁Despite ▁these ▁efforts ▁by ▁research ers , ▁these ▁projects ▁have ▁remained ▁in ▁the ▁pre cl in ical ▁stage . ▁ ▁Kn own ▁rib oz ym es ▁Well ▁valid ated ▁naturally ▁occurr ing ▁rib oz yme ▁classes : ▁▁ ▁G IR 1 ▁branch ing ▁rib oz yme ▁ ▁gl m S ▁rib oz yme ▁ ▁Group ▁I ▁self - sp lic ing ▁intr on ▁ ▁Group ▁II ▁self - sp lic ing ▁intr on ▁- ▁Sp lice os ome ▁is ▁likely ▁derived ▁from ▁Group ▁II ▁self - sp lic ing ▁rib oz ym es . ▁ ▁H air pin ▁rib oz yme ▁ ▁Ham mer head ▁rib oz yme ▁ ▁HD V ▁rib oz