1.von Willebrand disease with G4022A mutation (vWd Sungnam): a case report.
Kyung Soon SONG ; Shin Heh KANG ; Myung Seo KANG ; Young Sook PARK ; Jong Rak CHOI ; Hyun Kyung KIM ; Quhen PARK
Journal of Korean Medical Science 1999;14(1):93-96
A 10-year-old male patient affected by type 2 von Willebrand disease (vWD) and his family members were investigated by hemostatic and molecular genetic studies. The propositus, who experienced frequent bleeding episodes, was characterized by a normal level of von Willebrand factor (vWF) antigen (54%), reduced vWF ristocetin cofactor activity (5%), decreased factor VIII clotting activity (25%) and absent high molecular weight multimers in the plasma. An exon 28 fragment coding for the A1 and A2 domains was amplified by polymerase chain reaction and sequenced. We found a heterozygous mutation (G4022A), producing an additional PstI restriction site, which resulted in the substitution of Arg578Gln. Family studies, including the parents and a brother, were negative for this mutation and vWF abnormalities were not observed. We confirmed that G to A mutation in the region of the platelet glycoprotein Ib binding domain of vWF causes the qualitative type 2 defect in von Willebrand disease.
Alanine/genetics*
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Case Report
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Child
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Glycine/genetics*
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Human
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Male
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Point Mutation*
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von Willebrand Disease/genetics*
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von Willebrand Factor/genetics*