▁gene . ▁AR T 4 ▁has ▁also ▁been ▁designated ▁as ▁CD 2 9 7 ▁( cluster ▁of ▁different iation ▁ 2 9 7 ). ▁ ▁Function ▁▁ ▁This ▁gene ▁enc odes ▁a ▁protein ▁that ▁contains ▁a ▁mon o - AD P - rib os yl ation ▁( ART ) ▁mot if . ▁It ▁is ▁a ▁member ▁of ▁the ▁AD P - rib os yl trans fer ase ▁gene ▁family ▁but ▁en zym atic ▁activity ▁has ▁not ▁been ▁demonstrated ▁experiment ally . ▁Ant ig ens ▁of ▁the ▁D omb rock ▁blood ▁group ▁system ▁are ▁located ▁on ▁the ▁gene ▁product , ▁which ▁is ▁g ly cos yl ph osph at id y lin os it ol - anch ored ▁to ▁the ▁er yth ro cy te ▁memb rane . ▁Alle lic ▁variants , ▁some ▁of ▁which ▁lead ▁to ▁ad verse ▁trans f usion ▁re actions , ▁are ▁known . ▁ ▁Blood ▁group ▁ant ig ens ▁▁ ▁Several ▁ant ig ens ▁have ▁been ▁recogn ised ▁in ▁this ▁family . ▁These ▁are ▁DO * A , ▁DO * J O 1 , ▁DO * A - W L , ▁DO * DO Y A , ▁DO * B , ▁DO * B - W L , ▁DO * B - SH - Q 1 4 9 K , ▁DO * B -( W L )- I 1 7 5 N , ▁DO * H Y 1 , ▁DO * H Y 2 ▁and ▁DO * DO MR . ▁ ▁Model ▁organ isms ▁Model ▁organ isms ▁have ▁been