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 Background and Objectives

 Von Willebrand Disease (vWD) type 3 is an inherited disease characterized by severe clinical manifestations due to haemostatic abnormalities. Because of the autosomal recessive pattern of its inheritance, the disease is more frequent in regions with the high rate of consanguine marriages. We have previously demonstrated that despite various mutations of the gene, the Q793X mutation in exon 18 is more frequent in Iranian vWD patients. We have developed two assays to further investigate this mutation among Iranian patients.

 Materials and Methods

 The Q793X mutation status was studied in 15 vWD type 3 patients and 30 normal individuals by ARMS-PCR and real-time PCR assays. Melting curve analysis was performed after each real-time PCR experiment. To confirm the results of assays, all amplified gene fragments were sequenced.

 Results

 Three out of 15 patients were previously diagnosed as having Q793X mutation in homozygote status. This was further confirmed by the ARMS-PCR and real-time PCR assays. Interestingly, the mutation was also found in 2 other unrelated patients with unknown mutations. Heterozygote status for the mutation was not detected in normal controls.

 Conclusions

 Q793X mutation in vWF gene is common in Iranian population. However, a particular demographic distribution of the mutation was not observed in this study. Both assays successfully detected the mutation, although each assay has its own advantages and drawbacks. It is up to each laboratory to choose either assay based on their facilities and expertise.