[DNA analysis for the kininogen gene of patients with kininogen deficiency in Japan]

The kininogen (KGN) gene status was examined in 4 families with both high molecular weight (HMW) and low molecular weight (LMW) KGM deficiency and one family with only HMW-KGN deficiency reported in Japan. No abnormal HMW-KGN or LMW-KGN was detected in those with these deficiencies by immunoblot analysis using monoclonal antibodies (HKG-H12, HKG-L7, HKG-L17) for human HMW-KGN. HMW-DNA prepared from peripheral blood leucocytes was digested with endonuclease, EcoRI, Bam HI, Hind III, Sca I, Bg1II, Xba I, Msp I, Pst I, Hpa I, PvuII, HaeIII, Rsa I, Alu I, or Taq I, and studied by Southern blot analysis with human LMW prekininogen cDNA (phKG 36) as a probe. A gross deletion or insertion of the KGN gene was not detected in those with both HMW- and LMW-KGN deficiencies. On the other hand, partial defect in intron 7 (G) was found in those with only HMW-KGN deficiency, suggesting that this defect might be related to abnormality of the alternative RNA splicing events for HMW-prekininogen mRNA.