PCR-SSCP analysis of exon 7 of the GPIIIa gene. A 165-bp DNA fragment corresponding to exon 7 of the GPIIIa gene was amplified by PCR using genomic DNA as a template and subjected to SSCP. Lane 1, control DNA; lane 2, father of the patient HS heterozygous for GT. The positions of the shifted bands observed with DNA of the patient's father are indicated.