title: Two novel factor V null mutations associated with activated protein C resistance phenotype/genotype discrepancy.
abstract: Activated protein C (APC) resistance phenotype/genotype discrepancy is a very rare event. The objective of this study was to characterize the molecular mechanisms in two cases of APC phenotype/genotype discrepancy. An approach using direct sequencing of each exon and splicing junctions of the factor V gene showed that two novel factor V null mutations combined with heterozygous factor V Leiden mutation were responsible for this discrepancy. Our results suggest the necessity to use both phenotypic and genotypic analyses in some cases to determine an accurate diagnosis.
authors.affiliation: Laboratoire d'Hémostase, Hôpital Edouard Herriot, Lyon, France. ydargaud@univ-lyon1.fr
authors.forename: Yesim
authors.initials: Y
authors.lastname: Dargaud
authors.forename: Marie C
authors.initials: MC
authors.lastname: Trzeciak
authors.forename: Sandrine
authors.initials: S
authors.lastname: Meunier
authors.forename: Christele
authors.initials: C
authors.lastname: Angei
authors.forename: Dorothee
authors.initials: D
authors.lastname: Pellechia
authors.forename: Claude
authors.initials: C
authors.lastname: Négrier
authors.forename: Christine
authors.initials: C
authors.lastname: Vinciguerra
authors.forename: Yesmin
authors.initials: Y
authors.lastname: Dargaud
mesh_terms: D020016:Activated Protein C Resistance / Q000175:diagnosis / Q000235:genetics*; D002648:Child; D005165:Factor V / Q000235:genetics*; D005166:Factor V Deficiency / Q000235:genetics; D005260:Female; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D017422:Sequence Analysis, DNA; D019851:Thrombophilia / Q000235:genetics
chemical_list: D005165:Factor V