PCR-SSCP analysis of the G-CSFR cytosolic domain. The PCR was performed with primers FW4 and RV6 as described in Materials and Methods. The RT-PCR products from 4 patients (Patients 1 to 4) and normal controls (control) underwent polyacrilamide gel electrophoresis for 3 hours, and the bands were visualized by the silver-staining method.