A family with factor X deficiency from Argentina

Abstract

The objective was to investigate a family from Argentina. The proposita was a 51-year-old woman who had a moderate bleeding tendency. Some of her children showed a mild bleeding tendency. Her mother and the husband were asymptomatic. Clotting, immunological and molecular biology techniques were used. Partial thromboplastin, prothrombin, Russell Viper venom-clotting times were moderately prolonged in the proposita, whereas they were slightly prolonged in the children and in her mother. Factor X (FX) activity was about 2-3% of normal in all assay systems. FX antigen was less than 5%. Other clotting factors and platelet were normal. Genetic analysis showed a compound heterozygosis: combination of a 'new' mutation (Gln138Arg) with an already known mutation (Glu350Lys). The children had intermediate FX levels (35-63% of normal) and were carriers of one of the two mutations present in the proposita. This is the first observation of a FX deficiency in Argentina.

Mutations Seen in Families with Factor X Deficiency Composed of Only Heterozygous Patients who Present a Bleeding Tendency

“…When needed, assays were repeated in Padua on fresh frozen plasma as previously reported. [7,8] FX activity was carried out using tissue thromboplastin, activated partial thromboplastin, and a mixture of Russell viper venom and cephalin. FX antigen was evaluated by Asserachrom FX (Stago Laboratories, Asniers, France).…”

“…Genetic analysis was carried out as previously reported. [7] Briefly, genomic DNA was prepared from leukocytes by standard procedures. Amplification of exon 1 through exon 8 and respective spice junctions of the FX gene was performed using oligonucleotide primer kindly supplied by Dr. James H. (Tyler, TX, USA) and other acquired from Invitrogen (Carlsbad, CA, USA).…”

Plasma‐derived human factor X concentrate for the treatment of patients with hereditary factor X deficiency

“…Heterozygous individuals may be asymptomatic or have mild or moderate disease. [7][8][9] Most identified F10 mutations are missense mutations, although insertions, deletions and splicing mutations are also observed. [9][10][11] Genetic variants of the F10 gene can be found online.…”

“…Individuals with a severe bleeding phenotype generally have homozygous or compound heterozygous mutations in the F10 gene. Heterozygous individuals may be asymptomatic or have mild or moderate disease 7–9 . Most identified F10 mutations are missense mutations, although insertions, deletions and splicing mutations are also observed 9–11 .…”