[Investigation of Humoral and Cellular Immunity in TOBB ETÜ Hospital Workers After Three Doses of CoronaVac Vaccination and after One Dose of Comirnaty Vaccination Following Two Doses of CoronaVac]. / TOBB ETÜ Hastanesi Çalisanlarinda Üç Doz CoronaVac ile Iki Doz CoronaVac ve Bir Doz Comirnaty Asisi Sonrasi Humoral ve Hücresel Immünite Düzeylerinin Incelenmesi.

The Coronavirus disease 2019 (COVID-19) pandemic still continues around the world by making peaks with different variants. In the fight against COVID-19, vaccination is currently the only protective measure. In Turkey, vaccination started firstly in healthcare workers on 13 January 2021 with the CoronaVac (Sinovac Biotech, Chinese) vaccine, and booster doses were administered with the CoronaVac and Comirnaty vaccines in July 2021. In this cross-sectional study, it was aimed to determine the humoral and cellular immunity levels of the employees of the TOBB ETU Hospital 2.5-3.5 months after three doses of vaccination and identify the effective factors. With the power analysis that was conducted with the G*Power software, it was determined to be suitable to include 40 TOBB ETU Hospital workers who had their third dose with the CoronaVac vaccine and 60 workers of the same hospital who had their third dose with the Comirnaty (Pfizer Biontech, Germany) vaccine, and age- and sex-matching was considered by selecting 60 workers randomly from among 223 workers who had Comirnaty as their third dose. The study excluded individuals who had a previous COVID-19 infection or had a positive PCR test result. After collecting blood samples on 18-22 October 2021, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immunoglobulin G levels were studied with the chemiluminescence immunoassay method using a Beckman-Access device (Beckman Coulter Inc., CA, USA) for humoral immunity, and T-SPOT test (T-SPOT. COVID SARS-CoV-2 test-Oxford Immunotec, Singapur) was carried out for cellular immunity. Additionally, demographic data, habits, personal information such as weight and height, reasons for choosing the vaccine and post-vaccine side effects were obtained through the data collection form. Data collection was completed on 29 November 2021. As a result, among the healthcare workers who had received their third dose of vaccine with Comirnaty and CoronaVac; while 25% of those who received three doses of CoronaVac had humoral immunity, 93.3% humoral immunity was determined in the heterogeneous vaccine group with two doses of CoronaVac and one dose of Comirnaty vaccine (p<0.05). Cellular immunity was found to be higher (88.3%, 70%) in those who received the heterologous vaccine than those who completed three doses of the same vaccine (p<0.05). In the heterogeneous vaccination group consisting of the healthcare workers who had their third vaccine dose with Comirnaty and those who had it with CoronaVac, humoral and cellular immunity levels were found high. Among the participants whose humoral immunity was found negative, cellular immunity was present in 75% of those who had Comirnaty as their third dose and 63.3% of those who had CoronaVac. While no significant relationship was found between immunity levels and age, sex or body mass index (BMI), the levels of both forms of immunity were lower in those who had chronic diseases. Among the participants, physicians preferred the third dose of Comirnaty vaccine at a rate of 71.4% and laboratory workers preferred this vaccine at a rate of 80% according to the workplace. In the third dose vaccine preference reasons, it was stated that 55% would continue with the same vaccine, experience fewer side effects, 44% provide more immunity and 9% do not prevent going abroad. The incidence of side effects after the third dose of vaccine was 53% higher in those who received the Comirnaty vaccine than in those who received CoronaVac (35%). Based on these data, it was concluded that heterologous vaccination should be preferred in vaccination strategies, and knowing cellular immunity levels is important for the decision. There is a need for more comprehensive and follow-up studies on how long humoral and especially cellular immunity lasts.

Identification of novel TUBB1 variants in patients with macrothrombocytopenia.

Background/aim: Macrothrombocytopenia is an autosomal-dominant disorder characterized by increased platelet size and a decreased number of circulating platelets. The membrane skeleton and the link between actin filaments of the skeleton and microtubules, which consist of alpha and beta tubulin [including the tubulin beta-1 chain (TUBB1)] heterodimers, are important for normal platelet morphology, and defects in these systems are associated with macrothrombocytopenia. Materials and methods: In this study, we sequenced the exons of the TUBB1 gene using DNA isolated from the peripheral blood samples of healthy controls (n = 47) and patients with macrothrombocytopenia (n = 37) from Turkey. The TUBB1 expression levels in fractioned blood samples from patients and healthy controls were analyzed by RT-qPCR and Western blot. Microtubule organization of the platelets in the peripheral blood smears of patients, and in mutant TUBB1-transfected HeLa cells, were analyzed by immunofluorescence staining. Results: A new TUBB1 c.803G>T (p.T178T) variant was detected in all of the control and patient samples. Importantly, we found 3 new heterozygous TUBB1 variants predicting amino acid substitutions: G146R (in 1 patient), E123Q (in 1 patient), and T274M (in 4 patients); the latter variant was associated with milder thrombocytopenia in cancer patients treated with paclitaxel. Ectopic expression of TUBB1 T274M/R307H variant in HeLa cells resulted in irregular microtubule organization. Conclusion: Further clinical and functional studies of the newly identified TUBB1 variants may offer important insights into their pathogenicity in macrothrombocytopenia.

Genetic Analysis of Afibrinogenemia and Hypofibrinogenemia: Novel Mutations in the FGB Gene in the Turkish Population.

INTRODUCTION: Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen. Hypofibrinogenemia is characterized by fibrinogen levels <1.5 g/L. OBJECTIVE: In this study, we analyzed fibrinogen beta chain gene mutations in Turkish afibrinogenemia and hypofibrinogenemia patients. METHODS: We evaluated 20 afibrinogenemia and hypofibrinogenemia patients and 80 healthy controls. We have sequenced all exons of the FGB gene using the DNA isolated from the peripheral blood samples of patients and controls. RESULTS AND CONCLUSION: We found a nonsense mutation in exon 4 at nucleotide 630 that encoded serine amino acid, and in the same exon a missense mutation of T to C at nucleotide 647, resulting in a transition from leucine to proline (p.L198P) in a child with hypofibrinogenemia. These mutations have been shown for the first time in the same patient of Turkish descent. Furthermore, there was a novel heterozygous guanine-to-adenine nucleotide change in exon 3. This caused the change of arginine amino acid to threonine amino acid at position 136 (p.A136T) in a protein, which has not been described in the literature before.

Effects of Ankaferd Hemostat on Helicobacter pylori strains and antibiotic resistance

Background/aim: Ankaferd hemostat (ABS; Ankaferd blood stopper, Istanbul, Turkey) is a folkloric medicinal plant extract. The aim of this study was to determine the effect of Ankaferd hemostat (ABS) on the fate of Helicobacter pylori strains. The study also aims to determine alterations in the antimicrobial resistance of three different H. pylori strains in response to ABS exposure. Materials and methods: H. pylori Strain 1 was obtained from the culture collection ATCC 43504 and passaged three times for viability. Strain 2 was isolated from a gastric ulcer patient and Strain 3 was isolated from a gastritis patient. 1% of ABS was added to all of the strains and antimicrobial susceptibility was observed on 30 and 60 min after application. Results: The efficacy of ABS solutions in achieving significant logarithmic reduction in foodborne pathogens of H. pylori was observed in this study. This study showed that ABS has antibacterial (Anti-H. pylori) effects. Conclusion: Our present study indicated, for the first time, that ABS could act against H. pylori. ABS is clinically used for the management of GI bleeding due to benign and malignant GI lesions. Thus, the possible anti-H. pylori effect of ABS shall expand the therapeutic spectrum of the drug in GI lesions in relation to H. pylori infection such as peptic ulser disease (PUD) and lymphoid tissue (MALT) lymphomagenesis.

Frequency of vitamin K oxidoreductase complex subunit-1 (VKORC1) polymorphisms and warfarin dose management in patients with venous thromboembolism.

Warfarin works by inhibiting VKORC1, so polymorphisms of this gene modify the required drug dose. The aim of this study is to examine the relation between therapeutic weekly dose of warfarin and C1173T/G1639A polymorphism of VKORC1 in patients with VTE. Seventy-five patients with VTE were enrolled. Weekly warfarin doses and time (day) to reach therapeutic INR were evaluated retrospectively along with VKORC1-C1173T and G1639A alleles. The mean weekly warfarin dose was lower and time to reach therapeutic INR was shorter in homozygote alleles (AA and TT) (p < 0.05). The multivariate regression model was produced, R2 = 0.05% for age (p = 0.04), R2 = 6% for VKORC1 (p = 0.03), the model for estimating warfarin dose R2 = 17% (p > 0.05). In particular, patients who need overdose of warfarin or whose bleeding score is high, study of these polymorphisms can be considered.

Enlarging the gene-geography of Europe and the Mediterranean area to STR loci of common forensic use: longitudinal and latitudinal frequency gradients.

BACKGROUND: Tetranucleotide Short Tandem Repeats (STRs) for human identification and common use in forensic cases have recently been used to address the population genetics of the North-Eastern Mediterranean area. However, to gain confidence in the inferences made using STRs, this kind of analysis should be challenged with changes in three main aspects of the data, i.e. the sizes of the samples, their distance across space and the genetic background from which they are drawn. AIM: To test the resilience of the gradients previously detected in the North-Eastern Mediterranean to the enlargement of the surveyed area and population set, using revised data. SUBJECTS AND METHODS: STR genotype profiles were obtained from a publicly available database (PopAffilietor databank) and a dataset was assembled including >7000 subjects from the Arabian Peninsula to Scandinavia, genotyped at eight loci. Spatial principal component analysis (sPCA) was applied and the frequency maps of the nine alleles which contributed most strongly to sPC1 were examined in detail. RESULTS: By far the greatest part of diversity was summarised by a single spatial principal component (sPC1), oriented along a SouthEast-to-NorthWest axis. The alleles with the top 5% squared loadings were TH01(9.3), D19S433(14), TH01(6), D19S433(15.2), FGA(20), FGA(24), D3S1358(14), FGA(21) and D2S1338(19). These results confirm a clinal pattern over the whole range for at least four loci (TH01, D19S433, FGA, D3S1358). CONCLUSIONS: Four of the eight STR loci (or even alleles) considered here can reproducibly capture continental arrangements of diversity. This would, in principle, allow for the exploitation of forensic data to clarify important aspects in the formation of local gene pools.

The genetic basis of asymptomatic codon 8 frame-shift (HBB:c25_26delAA) ß(0) -thalassaemia homozygotes.

Two 21-year old dizygotic twin men of Iraqi descent were homozygous for HBB codon 8, deletion of two nucleotides (-AA) frame-shift ß(0) -thalassaemia mutation (FSC8; HBB:c25_26delAA). Both were clinically well, had splenomegaly, and were never transfused. They had mild microcytic anaemia (Hb 120-130 g/l) and 98% of their haemoglobin was fetal haemoglobin (HbF). Both were carriers of Hph α-thalassaemia mutation. On the three major HbF quantitative trait loci (QTL), the twins were homozygous for G>A HBG2 Xmn1 site at single nucleotide polymorphism (SNP) rs7482144, homozygous for 3-bp deletion HBS1L-MYB intergenic polymorphism (HMIP) at rs66650371, and heterozygous for the A>C BCL11A intron 2 polymorphism at rs766432. These findings were compared with those found in 22 other FSC8 homozygote patients: four presented with thalassaemia intermedia phenotype, and 18 were transfusion dependent. The inheritance of homozygosity for HMIP 3-bp deletion at rs66650371 and heterozygosity for Hph α-thalassaemia mutation was found in the twins and not found in any of the other 22 patients. Further studies are needed to uncover likely additional genetic variants that could contribute to the exceptionally high HbF levels and mild phenotype in these twins.

Novel mutations of integrin αIIb and ß3 genes in Turkish children with Glanzmann's thrombasthenia.

Glanzmann's thrombasthenia (GT) is an inherited disorder of platelet aggregation, characterized by qualitative and quantitative defect on platelet αIIbß3 integrin (GpIIb/IIIa), resulting in lifelong bleeding tendency due to defective platelet plug formation. The αIIb gene (ITGA2B) and ß3 gene (ITGB3) are closely located at chromosome 17q21.31-32. ITGA2B consist of 30 exons and encoding α chain, whereas ITGB3 has 15 exons and encoding ß chain. Until now, according to the Human Gene Mutation Database (HGMD), 138 mutations at ITGA2B gene and 101 mutations at ITGB3 gene have been identified. We aimed to determine whether there was any mutation in the ITGA2B and ITGB3 genes, and a correlation between clinical phenotype and genotype in Turkish GT patients. We examined 20 patients with GT followed at the Department of Pediatric Hematology, Meram Faculty of Medicine, for Clinical and Laboratory Findings and Molecular Genetic Analysis. Peripheral blood was collected from patients, and a written informed consent for genetic analysis was obtained from parents. DNA was isolated from by proteinase K and phenol/chloroform extraction. ITGA2B and ITGB3 genes were screened by polymerase chain reaction. There were 12 females and 8 males with a median age of 15.25 years. Major clinical presentations of these patients were mucocutaneous bleedings. The most common bleeding type was epistaxis (85%). Life-threatening bleedings were seen in five patients. Seven (35%) patients showed various mutations in the ITGA2B or ITGB3 genes. We detected four novel mutations in three different regions and two mutations defined previously within the ITGA2B gene. These changes are at exon 4; c.570 T > G alteration, at exon 13 c.1277 T > A, c.1291 T > G alterations, at exon 19 c.1921A > G alterations. And from the start point of exon 14, behind 107 bases, we detected a heterozygous alteration at Thymine to Guanine. According to PolyPhen Database Program and NCBI Multiple Alignment Tool Database, four transitions are conserved at evolutionary process, so we can say that these transitions are novel mutations. c. 468T > G alteration at exon 4 and c. 1378 T > A alteration at exon 13 were reported to HGMD previously. Screening the exons of the ITGB3 gene from the same patient groups, we reported a novel missense mutation at exon 5, at nucleotide 680. No correlation was found between clinical phenotype and genotype. These mutations were described for the first time in Turkish population, and all novel mutations are not defined previously. Furthermore, collaborative studies are needed for the population point of view.

An analysis of the levels of the soluble form of the endothelial protein C receptor in children with Henoch-Schönlein Purpura.

The pathogenesis of Henoch-Schönlein Purpura (HSP) has not been clearly defined. Inflammatory cytokines have been associated with HSP but there are only a few reports that have focused on coagulation. The endothelial protein C receptor (EPCR), which has anticoagulant and antiinflammatory activity, is the key component of the protein C pathway. Recent studies have implicated the soluble form of EPCR (sEPCR) in Wegener's granulomatosis, Behçet's disease, and systemic lupus erythematosus. The aim of this study was to evaluate the levels of sEPCR in HSP children. Twenty-two children with HSP and 17 healthy children were included. We found no significant differences (P > .05) between patient and control groups in the levels of von Willebrand factor and thrombomodulin. The median sEPCR values in the HSP group were lower than the control group (79 vs. 102 ng/mL, respectively) (P > .05). The mean sEPCR value in HSP patients with severe abdominal pain was lower than without (88.8 ± 54.9 vs. 108.2 ± 66.3 ng/mL, respectively) (P > .05). In addition, the mean IL-6 serum levels were significantly elevated in HSP patients during the acute stage of HSP (2.1 ± 1.7 vs. 1.5 ± 1.2 pg/mL, P = .038). We also observed a slight negative correlation between the levels of sEPCR and IL-6 (R = -.135, P > .05). To our knowledge, this was the first study to analyze sEPCR levels in HSP. Our results did not conclusively identify a direct role of sEPCR in HSP, but our findings warrant further investigations, especially in severe HSP cases characterized by gastrointestinal bleeding or renal involvement.

A degradation-sensitive anionic trypsinogen (PRSS2) variant protects against chronic pancreatitis.

Chronic pancreatitis is a common inflammatory disease of the pancreas. Mutations in the genes encoding cationic trypsinogen (PRSS1) and the pancreatic secretory trypsin inhibitor (SPINK1) are associated with chronic pancreatitis. Because increased proteolytic activity owing to mutated PRSS1 enhances the risk for chronic pancreatitis, mutations in the gene encoding anionic trypsinogen (PRSS2) may also predispose to disease. Here we analyzed PRSS2 in individuals with chronic pancreatitis and controls and found, to our surprise, that a variant of codon 191 (G191R) is overrepresented in control subjects: G191R was present in 220/6,459 (3.4%) controls but in only 32/2,466 (1.3%) affected individuals (odds ratio 0.37; P = 1.1 x 10(-8)). Upon activation by enterokinase or trypsin, purified recombinant G191R protein showed a complete loss of trypsin activity owing to the introduction of a new tryptic cleavage site that renders the enzyme hypersensitive to autocatalytic proteolysis. In conclusion, the G191R variant of PRSS2 mitigates intrapancreatic trypsin activity and thereby protects against chronic pancreatitis.

A truncating mutation in SERPINB6 is associated with autosomal-recessive nonsyndromic sensorineural hearing loss.

More than 270 million people worldwide have hearing loss that affects normal communication. Although astonishing progress has been made in the identification of more than 50 genes for deafness during the past decade, the majority of deafness genes are yet to be identified. In this study, we mapped a previously unknown autosomal-recessive nonsyndromic sensorineural hearing loss locus (DFNB91) to chromosome 6p25 in a consanguineous Turkish family. The degree of hearing loss was moderate to severe in affected individuals. We subsequently identified a nonsense mutation (p.E245X) in SERPINB6, which is located within the linkage interval for DFNB91 and encodes for an intracellular protease inhibitor. The p.E245X mutation cosegregated in the family as a completely penetrant autosomal-recessive trait and was absent in 300 Turkish controls. The mRNA expression of SERPINB6 was reduced and production of protein was absent in the peripheral leukocytes of homozygotes, suggesting that the hearing loss is due to loss of function of SERPINB6. We also demonstrated that SERPINB6 was expressed primarily in the inner ear hair cells. We propose that SERPINB6 plays an important role in the inner ear in the protection against leakage of lysosomal content during stress and that loss of this protection results in cell death and sensorineural hearing loss.

A novel protein C inhibitor gene mutation in pediatric stroke patients after bone marrow transplantation.

Protein C inhibitor is a heparin dependent serine protease inhibitor found in human plasma, urine and other body fluids. It was originally identified as an inhibitor of activated protein C. Stroke is an important cause of morbidity and mortality in the pediatric age group. In this study we analyzed the protein C inhibitor gene mutations in Turkish pediatric stroke patients. We found a missense mutation of G to A at nucleotide 6760 in exon 2, resulting in a transition serine to asparagine (p.Ser188Asp) and in a child and his father and also we found same alteration in exon 2 in an another pediatric stroke case following bone marrow transplantation.

Risk of venous thromboembolism associated with single and combined effects of Factor V Leiden, Prothrombin 20210A and Methylenetethraydrofolate reductase C677T: a meta-analysis involving over 11,000 cases and 21,000 controls.

Genetic and environmental factors interact in determining the risk of venous thromboembolism (VTE). The risk associated with the polymorphic variants G1691A of factor V (Factor V Leiden, FVL), G20210A of prothrombin (PT20210A) and C677T of methylentetrahydrofolate reductase (C677T MTHFR) genes has been investigated in many studies. We performed a pooled analysis of case-control and cohort studies investigating in adults the association between each variant and VTE, published on Pubmed, Embase or Google through January 2010. Authors of eligible papers, were invited to provide all available individual data for the pooling. The Odds Ratio (OR) for first VTE associated with each variant, individually and combined with the others, were calculated with a random effect model, in heterozygotes and homozygotes (dominant model for FVL and PT20210A; recessive for C677T MTHFR). We analysed 31 databases, including 11,239 cases and 21,521 controls. No significant association with VTE was found for homozygous C677T MTHFR (OR: 1.38; 95 % confidence intervals [CI]: 0.98-1.93), whereas the risk was increased in carriers of either heterozygous FVL or PT20210 (OR = 4.22; 95 % CI: 3.35-5.32; and OR = 2.79;95 % CI: 2.25-3.46, respectively), in double heterozygotes (OR = 3.42; 95 %CI 1.64-7.13), and in homozygous FVL or PT20210A (OR = 11.45; 95 %CI: 6.79-19.29; and OR: 6.74 (CI 95 % 2.19-20.72), respectively). The stratified analyses showed a stronger effect of FVL on individuals ≤ 45 years (p value for interaction = 0.036) and of PT20210A in women using oral contraceptives (p-value for interaction = 0.045). In this large pooled analysis, inclusive of large studies like MEGA, no effect was found for C677T MTHFR on VTE; FVL and PT20210A were confirmed to be moderate risk factors. Notably, double carriers of the two genetic variants produced an impact on VTE risk significantly increased but weaker than previously thought.

Blood group genotyping in multi-transfused patients.

BACKGROUND: In chronically transfused patients, the classical hemagglutination assays may be inaccurate in defining the RBC phenotypes of the patients due to previous transfusions. DESIGN: DNA samples from 39 multi-transfused patients including thalassemia and sickle cell disease were used for red blood cell genotyping. The Rh-Type and KKD-Type (BAGene, BAG Healthcare) were used to determine the polymorphisms associated with antigen expression for RHD, RHCE and Kell, Kidd, Duffy blood group systems, respectively. Results were compared with previously determined phenotyping results for RhD, RhCcEe and Kell by hemagglutination method. RESULTS: Nineteen out of the 37(51%) patients had discrepancies between genotyping and phenotyping results in a total of 25 alleles. In 12 patients, the discrepancies had the potential of alloimmunization. CONCLUSION: Blood group genotyping has vital importance in transfusion management of chronically transfused patients especially if the patients were not phenotyped before starting the initial transfusions.

Endothelial protein C receptor and pediatric arterial stroke.

OBJECTIVE: The aim of this study was to investigate the endothelial protein C receptor (EPCR) gene A3 haplotype and plasma soluble EPCR (sEPCR) levels in Turkish pediatric arterial stroke patients. MATERIALS AND METHODS: We analyzed 44 pediatric arterial stroke patients and 75 healthy controls. Following DNA isolation, genotyping of the A3 haplotype was determined via PCR and RFLP. Additionally, fasting sEPCR levels were determined via ELISA. RESULTS: There wasn't a significant difference in the sEPCR level between the control and patient groups, although the sEPCR level was higher in the patient group. We didn't observe a difference in the distribution of the CC and CG/GG genotypes between the control and patient groups. CONCLUSION: Further study on sEPCR levels at the onset of pediatric stroke is needed in order to reach a more definitive conclusion. CONFLICT OF INTEREST: None declared.

Genetic Profiling of Pediatric Patients with B-Cell Precursor Acute Lymphoblastic Leukemia.

B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is a heterogeneous leukemia subgroup. It has multiple sub-types that are likely to be classified by prognostic factors. Following a systematic literature review, this study analyzed the genes correlated with BCP-ALL prognosis ( IKZF1, PAX5, EBF1, CREBBP, CRLF2, JAK2, ERG, CXCR4, ZAP70, VLA4, NF1, NR3C1, RB1, TSLP, ZNRF1, and FOXO3A) , specifically their nucleotide variations and expression profiles in pediatric BCP-ALL samples. The study included 45 pediatric BCP-ALL patients with no cytogenetic anomaly and a control group of 10 children. The selected genes' hot-spot regions were sequenced using next-generation sequencing, while Polymorphism Phenotyping v2 and Supplemental Nutrition Assistance Program were used to identify pathogenic mutations. The expression analysis was performed using quantitative real-time polymerase chain reaction. The mutation analysis detected 328 variants (28 insertions, 47 indels, 74 nucleotide variants, 75 duplications, and 104 deletions). The most and least frequently mutated genes were IKZF1 and CREBBP , respectively. There were statistically significant differences between patients and controls for mutation distribution in eight genes ( ERG, CRLF2, CREBBP, TSLP, JAK2, ZAP70, FOXO3A, and NR3C1 ). The expression analysis revealed that JAK and ERG were significantly overexpressed in patients compared with controls (respectively, p = 0.004 and p = 0.003). This study combined genes and pathways previously analyzed in pediatric BCP-ALL into one dataset for a comprehensive analysis from the same samples to unravel candidate prognostic biomarkers. Novel mutations were identified in all of the studied genes.

The association of protease activated receptor 1 gene -506 I/D polymorphism with disease-free survival in breast cancer patients.

BACKGROUND: Recent data have shown that tumor development and dissemination may be regulated by procoagulant/anticoagulant axis. The aim of the present study was to search for an association of the protease activated receptor (PAR)1 gene -506 insertion/deletion (I/D), factor V Leiden (FVL), prothrombin (PT) G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T polymorphisms with disease-free survival (DFS) in breast cancer. METHODS: Genotyping of -506 I/D in the promoter region of PAR1 gene was performed by single-strand conformation polymorphism analysis and sequencing. FVL, PT G20210A, and MTHFR C677T were also determined by the method of polymerase chain reaction-based DNA analysis. Data regarding patient's age, menopausal status, tumor size, lymph node status, disease stage, tumor grade, estrogen and progesterone receptor, c-erb B2 expression, PAR1 -506 I/D, MTHFR C677T, FVL, and PT G20210A polymorphisms were examined by the univariate and multivariate analyses. RESULTS: Recurrent disease occurred in 29 patients (19.6 %) within a median of 20 months. It was found that tumor size, lymph node status, tumor stage, tumor grade, c-erbB2 expression, and PAR1 -506 I/D polymorphism were associated with DFS when Kaplan-Meier method was applied (P<.05). By Cox proportional hazards model, the presence of allele D at -506 locus (P=.0249) and small tumor size (P=.0001) were significant favorable prognostic factor, but c-erbB2 expression was an adverse prognostic factor (P=.0049). CONCLUSION: Our study suggested the protective effect of the allele D at -506 locus of PAR1 gene on the recurrence of breast cancer.