Detection of new polymorphic markers in the factor V gene: Association with factor V levels in plasma

B. Lunghi, L. Iacoviello, D. Gemmati, M. G. Dilasio, E. Castoldi, M. Pinotti, G. Castaman, R. Redaelli, G. Mariani, G. Marchetti, F. Bernardi

Research output: Contribution to journalArticlepeer-review


Three novel polymorphisms were found in the repeated region of the large exon 13 of factor V gene, one giving rise to a codon dimorphism (Ser1240) and two causing aminoacid substitutions (His1299Arg, Leu1257Ile). An increasing frequency of the Arg1299 (R2 allele) correlated with a decreasing mean plasma-factor V activity in the groups of subjects under study, which included 26 unrelated subjects with partial factor V deficiency. Family studies supported the co-inheritance both of low factor V activity and of R2 allele. The reduction of factor V activity associated with the R2 allele was not clinically symptomatic even in the homozygous condition and was characterized by a parallel reduction of antigen in plasma, in which abnormal molecules were not detected. Data suggest that the R2 allele represents a marker in linkage with an unknown defect rather than a functional polymorphism. These studies provide the first evidence of a genetic component in determining factor V levels in plasma and of a genetic linkage between the factor V gene and factor V deficiency. They also define specific haplotypes which are associated with factor V deficiency or with APC resistance (Arg506Gln) and are valuable tools for the study of factor V defects.

Original languageEnglish
Pages (from-to)45-48
Number of pages4
JournalThrombosis and Haemostasis
Issue number1
Publication statusPublished - Jan 1996

ASJC Scopus subject areas

  • Hematology


Dive into the research topics of 'Detection of new polymorphic markers in the factor V gene: Association with factor V levels in plasma'. Together they form a unique fingerprint.

Cite this