A Database of Polymorphisms in the von Willebrand Factor Gene and Pseudogene

Abstract

SummaryNucleotide sequence polymorphisms in the von Willebrand factor (vWF) gene are useful for genetic studies in von Willebrand disease (vWD). This database describes 33 known vWF polymorphisms distributed throughout the vWF gene. DNA sequence information is available for 21 of these sites. The most informative system is a tetranucleotide repeat polymorphism in vWF intron 40. Sixteen of these polymorphisms are within vWF exons, and approximately half of them also alter the encoded amino acid sequence. Many occur close to mutations that cause vWD. The high prevalence of vWF polymorphisms must be considered in the analysis of candidate vWD mutations. In addition to the vWF gene on chromosome 12, there is a partial unprocessed vWF pseudogene on chromosome 22 that corresponds to vWF exons 23 to 34. Three polymorphisms have been assigned to the vWF pseudogene. Because the vWF gene and pseudogene have diverged only ∼3.1% in DNA sequence, correct assignment of polymorphisms to either locus can be difficult in the region of homology. This problem has been solved in some cases by comparison of the published sequences and predicted restriction maps for the gene and pseudogene.