Congenital plasminogen deficiency caused by a Ser572 to Pro mutation

We used a polymerase chain reaction (PCR) strategy and restriction fragment polymorphism analysis to evaluate all 19 exons of the plasminogen (PLG) gene in a Japanese patient with congenital PLG deficiency and her family members. She presented with cerebral infarction. Sequence analysis following amplification of each exon and its flanking regions showed a single T to C transition in exon 14, which changed a Ser572 codon (TCC) to Pro572 codon (CCC). Since this mutation generates a new Fok I site, the Fok I digestion pattern of the PCR-amplified exon 14 fragments from each family member was analyzed. In all cases, the patterns were consistent with the activities and antigen levels of plasma PLG in those members. Furthermore, all PCR-amplified exon 14 fragments from 15 normal individuals were not restricted with Fok I endonuclease. We conclude that a T to C transition in exon 14 identified in the propositus is responsible for PLG deficiency inherited in this Japanese family with thrombotic episodes.