Analysis of acidic PRP isoforms in human PS. (A) Ornstein Davis gel electrophoresis of PRP isoforms. Lanes 1–6, pure and semipure PRP isoforms (20 μg protein/lane); lane 7, Pa dimer (20 μg) incubated with DTT. (B) Ornstein Davis gel electrophoresis of PS (50 μL/lane) from two subjects per group. (C) Agarose gel (2.5%) of PCR products obtained after amplification with primers specific for the PRH1 locus. Lane 1, bp standard; lane 2–9, PCR products representing three products: Db (416 bp) and PIF/Pa (each 353 bp, indistinguishable).