PCR-amplified fragments and sequence analyses of control and patient RNA and DNA samples. (A) RT-PCR amplification of RNA extracted from normal control (N) and patient (LW) platelets. Using primers A and C (Table 1), a 424-bp fragment was cloned and sequenced. Arrows indicate the T (normal) to C (patient) nucleotide base change. (B) PCR amplification of DNA extracted from peripheral mononuclear cells isolated from a normal control (N) and the patient (LW). Using primers specific for amplification of GPIIb exon 6, the 245-bp fragments were directly sequenced as described previously. Arrows indicate the T (normal) to C (patient) nucleotide base change. No normal sequence was identified in the patient's DNA.