Identification of a His54Gln substitution in von Willebrand factor from a patient with defective binding of factor VIII.
A patient with type 2N ("Normandy" variant) von Willebrand's disease is described. Her von Willebrand factor level was borderline low, while her factor VIII was markedly decreased to 7%. Her plasma von Willebrand factor demonstrated a decreased ability to complex with factor VIII in vitro, binding less than 10% when compared to normal plasma von Willebrand factor. The factor VIII released into the circulation after the patient received DDAVP had a shortened survival in vivo. Nucleotide sequence analysis revealed a T-to-A transition at nucleotide 2451 on both alleles. This transition results in a substitution of Gln for His at amino acid 54 in the mature subunit of von Willebrand factor.
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Hematology Section, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, Maryland 20892, USA.
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D000328:Adult; D000483:Alleles; D001483:Base Sequence; D003894:Deamino Arginine Vasopressin / Q000627:therapeutic use; D005169:Factor VIII / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D017354:Point Mutation; D011485:Protein Binding; D014842:von Willebrand Diseases / Q000235:genetics*; D014841:von Willebrand Factor / Q000235:genetics* / Q000378:metabolism
D014841:von Willebrand Factor; D005169:Factor VIII; D003894:Deamino Arginine Vasopressin