Human Antithrombin Matched Antibody Pair

Methods routinely used for investigating the molecular basis of antithrombin (AT) deficiency do not detect large SERPINC1 rearrangements. Between 2000 and 2008, 86 probands suspected of having AT-inherited type I deficiency were screened for SERPINC1 mutations in our laboratory. Mutations causally linked to the deficiency were identified by sequencing analysis in 63 probands. We present here results of multiplex ligation-dependent probe amplification (MLPA) analysis performed in 22 of the 23 remaining probands, in whom sequencing had revealed no mutation. Large deletions, present at the heterozygous state, were detected in 10 patients: whole gene deletions in 5 and partial deletions removing either exon 6 (n = 2), exons 1-2 (n = 1) or exons 5-7 (n = 2) in 5 others. Exon 6 partial deletions are a 2,769-bp deletion and a 1,892-bp deletion associated with a 10-bp insertion, both having 5' and/or 3' breakpoints located within Alu repeat elements. In addition, we identified the 5' breakpoint of a previously reported deletion of exons 1-2 within an extragenic Alu repeat. Distinct mutational mechanisms explaining these Alu sequence-related deletions are proposed. Overall, in this series, large deletions detected by MLPA explain almost half of otherwise unexplained type I AT-inherited deficiency cases.

The primary aim was to determine frequencies of mutations related to risk of venous thrombosis in healthy Caucasians in Central Bohemia. In a cohort of 1527 healthy individuals the frequency of risk alleles for the mutations FV Leiden and FII 20210G> A was 4.5 % and 1.3 %, respectively. Frequency of 4G PAI- 1 allele was 55.5 %. Genotype frequencies were: GG 91.03 %, GA 8.91 %, and AA 0.07 % for FV Leiden; GG 97.45 %, GA 2.49 %, and AA 0.07 % for FII 20210G> A; 4G/4G 30.26 %, 4G/5G 50.56 %, and 5G/5G 19.19 % for PAI-1. Frequency of the risk allele A in polymorphism SERPINC1 (IVS + 141G > A) was 11.3 %, and frequencies of genotypes were as follows: GG 78.36 %, GA 20.66 %, and AA 0.98 %. Frequency of the risk allele T for polymorphism GP6 13254T> C was 87.7 %, and frequencies of genotypes were as follows: TT 77.14 %, TC 21.15 %, and CC 1.70 %. Frequency of the risk allele A in polymorphism CYP4V2 (Lys259Gln) was 65.2 %, and frequencies of genotypes were: CC 12.25 %, CA 45.12 %, and AA 42.63 %. All observed genotypes and alleles frequencies were without gender differences. Their occurrences confirm a relatively high prevalence of hereditary thrombophilia predisposition in the Czech Republic.