Determination of the regional assignment of the EPCR gene by FISH. Slides were prepared from phytohemagglutinin-stimulated peripheral-blood cultures and hybridized with biotin labeled PAC DNA. The chromosomes were background-stained with DAPI. The DAPI-banding pattern was enhanced and converted to greyscale with SmartCapture software to enable chromosome and band assignation (left panel). Hybridized PAC DNA was detected using fluorescein isothiocyanate (right panel). Specific fluorescent signals and the locus 20q11.2 are indicated by arrows.