passages.id: split_1_test_2580_passage
passages.type: progene_text
passages.text: Inhibitory receptor genes KIR2DL2 / 3 and KIR2DL1 were present in nearly all subjects sampled in this study , whereas their respective activating homologs , KIR2DS2 and KIR2DS1 , are each present in about half of the subjects .