Automated detection of the factor V Leiden mutation using the LCx microparticle enzyme immunoassay

The factor V Leiden mutation, a G-->A transition at position 1691. in exon 10 of the gene that codes for factor V,produces an Arg(506)Gln substitution and is the most common genetic risk factor for venous thrombosis. We have developed a rapid, sensitive, and specific method to detect the factor V Le iden mutation in genomic DNA from whole blood by PCR amplification and micr oparticle enzyme immunoassay detection using the Abbott LCx instrument We c ompared this automated method with the standard procedure using restriction endonuclease digestion of PCR products followed by gel electrophoresis in blinded experiments. In 130 patients (from Veterans Affairs medical centers ) with deep venous thromboses, including 24 heterozygotes with the factor V Leiden mutation, there was complete agreement between the two methods. The assay was also able to distinguish heterozygotes from homozygotes. This me thod, which carries a low potential for cross-contamination of samples, sho uld be a useful routine test for the factor V Leiden mutation in clinical l aboratories with sufficient demand for molecular diagnostic assays using th e LCx instrument.