using rhodamine-labelled antibodies directed against gamma-globin , fetal erythrocytes can be identified in fetal blood samples contaminated with maternal cells , and using fluorescein-labelled antibodies directed against beta-globin , the presence of beta-chains ( and thus hb-a ) may be determined in the same cells by double labelling immunofluorescence microscopy .
C0017033
gamma-globin
C0005221
beta-globin