Methylenetetrahydrofolate Reductase Mutation Research Articles

Thrombophilia investigation in Malaysian women with recurrent pregnancy loss

The status of thrombophilia in Asian women with recurrent pregnancy loss (RPL) is obscure and poorly understood. Numerous studies suggest the non-existence or extreme rarity of the two important thrombophilia markers, factor V Leiden (FVL) and prothrombin G20210A (PTG) mutations, in patients of Asian ancestries. Thus, the consensus that thrombophilia is rare among Asians and laboratory investigations is irrelevant. We therefore investigated Malaysian women with RPL for thrombophilia abnormalities. A total of 402 patients (RPL subjects) and 160 female controls were screened for FVL, PTG and methylene tetrahydrofolate reductase mutations using polymerase chain reaction, activated protein C resistance (APC-R) using clot-based tests, protein C and antithrombin using chromogenic tests, and protein S and antiphospholipid antibodies using enzyme-linked immunosorbent assays. APC-R was identified in 21.6% (87/402) of the RPL subjects. Of the 87 APC-R positive RPL subjects, 9.2% (8/87) were due to FVL, 51.7% (45/87) had protein S deficiency, 6.9% (6/87) had protein C deficiency, 6.9% (6/87) had combined protein S and protein C deficiencies, 1.1% (1/87) had antithrombin deficiency and 25.3% (22/87) had unidentifiable non-specific abnormalities. Antiphospholipid antibodies were identified in 4.2% (17/402) of the RPL subjects. FVL (2% = 8/402) and PTG (0.5% = 2/402) were identified in the Malay and Indian RPL subjects, but there were none in the Chinese subjects or the controls. Methylene tetrahydrofolate reductase was identified in 35.3% (142/402) of the RPL subjects. Thrombophilia was identified in more than one-quarter (26.6% = 107/402) of the RPL subjects. APC-R not caused by FVL mutation was the most common thrombophilia marker in Malaysians, whereas in Caucasians it was the APC-R due to FVL mutation. The identification of FVL and PTG mutations in Malaysian women with RPL disputes prevailing evidences suggesting its non-occurrence in patients with Asian ancestries.

An Unusual Melting Curve on a LightCycler Due to a New Mutation in Methylenetetrahydrofolate Reductase

Methylenetetrahydrofolate reductase (MTHFR; E.C. 1.5.1.20) catalyzes the reduction of 5,10-methylenetetrahydofolate to 5-methytetrahydrofolate, and its activity is affected by a number of polymorphisms and mutations, the best known being MTHFR c.677C > T (OMIM 607093.003). The c.677C > T mutation is often analyzed by melting curve analysis after real-time polymerase chain reaction. We observed in one patient upon dual hybridization probe analysis in a Roche LightCycler 1.2 an unusual melting curve peak at 53.4 degrees C instead of one expected at either 51.6 degrees C or 60.4 degrees C. We sequenced the region of MTHFR interrogated by the dual hybridization probes, which revealed a c.685A > G base substitution that would result in an Ile225Val substitution. In conclusion, we identified the cause of an unusual melting curve in a commonly used genotyping technique for MTHFR c.677C > T as due to a novel mutation highlighting the ability of melting analysis to identify new sequence variants.

Hypercoagulable State and Methylenetetra- hydrofolate Reductase (MTHFR) C677T Mutation in Patients with Beta-Thalassemia Major in Kuwait

Introduction: Patients with thalassemia major often present with a hypercoagulable state, the pathogenesis of which is still not understood. Materials and Methods: This study evaluates the risk factors for hypercoagulability in 50 β-thalassemia major patients and 50 healthy controls. Fasting total homocysteine, protein C (PC), protein S (PS), antithrombin (AT), activated protein C resistance (APCR) and lupus anticoagulant (LA) were assessed. MTHFR C677T mutation was determined. Results: Significant reductions in PC, PS and AT were noted in patients. Only 4% of the patients had hyperhomocysteinemia. Thirty-two percent of the patients were heterozygous and 4% were homozygous for MTHFR C677T mutation. Conclusion: The natural coagulation inhibitors PC, PS and AT were significantly reduced in patients with β-thalassemia major and were thus important risk factors for the hypercoagulable state, but hyperhomocysteinemia and MTHFR mutation do not seem to be significant risk factors for thromboembolic events.

Live Term Birth and Two Ongoing Viable Pregnancies with Therapeutic Enoxaparin and Aspirin After Failure of Prophylactic Enoxaparin and Aspirin in Two Women with Thrombophilia and Recurrent Pregnancy Loss.

Abstract 4184The combination of prophylactic heparin and low-dose aspirin was shown in the 1990s to improve pregnancy outcome in patients with antiphospholipid antibodies and recurrent pregnancy loss (RPL). Antiphospholipid antibodies induce placental thrombosis. When associations between hereditary thrombophilias and RPL were reported in the early 2000s, we and other physicians (Rodger MA J Obstr Gyn Canada 2002) began empirically prescribing prophylactic low molecular weight heparin, low-dose aspirin, or the combination to pregnant women with thrombophilia and unexplained RPL. We observed high live birth rates. Data emerged showing live birth rates of 70.2-94% in pregnant women with RPL treated with low-dose low molecular weight heparin and/or low-dose aspirin. Only one report has addressed treatment after failure of low-dose low molecular weight heparin: Brenner and colleagues (Thromb Haemost 2000) treated 3 pregnant women with multiple thrombophilic defects with enoxaparin 60 mg x 2/day after failure of enoxaparin 40 mg x 2/day; all 3 pregnancies yielded live births. We report cases of a live term birth and two ongoing viable pregnancies with therapeutic enoxaparin,1.5 mg/kg SC, (TEP) and aspirin after failure of prophylactic enoxaparin, 40 mg SC, (PEP) and aspirin in two women with thrombophilia and RPL.A 33 year-old woman with a history of 2 unexplained miscarriages at 6 weeks (Patient 1) and a 42 year-old woman with a history of 3 unexplained miscarriages at 8 weeks (Patient 2) presented in April 2006 and in August 2007 respectively. Uterine malformations, acquired uterine defects, and hormonal abnormalities were ruled out. Parental karyotypes were normal. Thrombophilia evaluation included: factor V Leiden, prothrombin gene mutation, methylene tetrahydrofolate reductase (MTHFR) gene mutation, fasting homocysteine, protein C, protein S, antithrombin, IgG anticardiolipin antibody, IgM anticardiolipin antibody, lupus anticoagulant, plasminogen activator inhibitor-1 (PAI-1), and PAI-1 4G/5G polymorphism. Positive results were: one copy each of the C677T and A1298C MTHFR mutations in Patient 1 and Patient 2; PAI-1 120 ng/mL and PAI-1 4G/4G polymorphism in Patient 2. The following describes the clinical course in both patients.Patient 1 was started on aspirin 81 mg daily and on clomiphene citrate to improve fertility. She conceived but miscarried at 7 weeks in June 2006. She underwent in vitro fertilization (IVF) in December 2006 while continuing on aspirin. She started on PEP daily within 24 hours of egg retrieval. She miscarried twins at 6 and 8&1/2 weeks. In May 2007, she conceived through IVF while continuing on aspirin. She started on TEP daily within 24 hours of egg retrieval. Anti-Xa level was monitored monthly. Enoxaparin was adjusted to maintain the anti-Xa level between 0.6 and 1.2 ui/mL. She delivered a healthy term baby on January 10, 2008. She continued to take aspirin daily. She conceived naturally in February 2009. She started on TEP daily with monthly anti-Xa monitoring when her pregnancy was confirmed. She currently has a live 24-week gestation.Patient 2 was started on aspirin 81 mg daily. She conceived through IVF in May 2008. She started on PEP daily within 24 hours of egg retrieval. She miscarried in a few weeks. She conceived through IVF in October 2008 while continuing on aspirin. She started on PEP daily within 24 hours of egg retrieval. After two weeks when her pregnancy was confirmed PEP was increased to TEP. She miscarried in a few weeks. She conceived in May 2009 through IVF while continuing on aspirin. TEP with monthly anti-Xa monitoring was started prior to IVF when she started her ovarian stimulation medications. She currently has a live 16-week gestation.Our report corroborates the findings by Brenner and colleagues of a benefit of an increased enoxaparin dose after failure of a low dose. It is possible that the higher dose leads to better control of a placental thrombotic state. While the timing of initiation of thromboprophylaxis has been established for natural pregnancies (aspirin is started pre-conception; enoxaparin is started at pregnancy confirmation or at detection of the fetal heartbeat), optimal time for initiation of thromboprophylaxis in IVF pregnancies has not been determined. Ovarian stimulation for IVF leads to a hyperestrogenic state which increases thrombotic risk. It is possible that starting TEP at the time of initiation of ovarian stimulation in Patient 2 enabled her ongoing viable second-trimester pregnancy by optimizing placental conditions. Disclosures:Off Label Use: Aspirin and enoxaparin during pregnancy to prevent recurrent fetal loss.

Methylenetetrahydrofolate Reductase Homozygous Mutation in a Young Boy with Cerebellar Infarction

Posterior circulation vascular occlusive disease in children is a rare and uncommonly reported event. Among the numerous risk factors, the methylenetetrahydrofolate reductase (MTHFR) mutation is considered to be a common genetic cause of thrombosis in adults and children. Recently, a link between the MTHFR mutation and cerebrovascular disorders was reported in children. Diffusion tensor imaging (DTI) is a great improvement on magnetic resonance imaging (MRI), making the in vivo anatomical and pathological study of the brain and its fibers possible. In our patient cerebellar infarction was associated with MTHFR mutation and, in a standard neurological examination, DTI revealed normal white matter tracts.

Is Familial Mediterranean Fever a Possible Cofactor for Budd‐Chiari Syndrome?

Budd-Chiari syndrome (BCS) is characterized by obstruction of hepatic venous outflow at any level of the hepatic veins or the inferior vena cava (IVC). Clinical presentation ranges from asymptomatic cases to fulminant hepatic failure or end-stage liver disease (1). Primary endophlebitis or congenital malformations may be responsible for BCS (1). Although several hypercoagulable states such as antithrombin III, protein C and S deficiency, factor V Leiden (FVL), and prothrombin gene 20210A mutations have been linked to BCS, recent data show that primary BCS is a multifactorial disease and the combination of several prothrombotic factors play a role in the development of thrombosis (1). Familial Mediterranean fever (FMF) is an autoinflammatory disorder characterized by episodic fever and polyserositis. Hypercoagulability has been recently reported in patients with FMF, yet thrombotic events were rarely reported in the literature. Although large vessel thrombosis in patients with FMF without amyloidosis is an unexpected event, an occurrence of superior vena cava thrombosis in a patient with FMF has also been reported (2-4). Our report is one of the few articles in the literature in which a major thrombotic event has occurred in the setting of FMF without amyloidosis.

PO17-TU-01 CNS manifestations in systemic sclerosis: a case report

polymorphisms: the prothrombin 20210 G→A, factor V Leiden G 1691A, plasminogen activator inhibitor (PAI) −6754G/5G, fibrinogen −455G→A, platelet receptors: GPIB (−5) T→C, GPIIIA L33P T→ C, GP IA C807T, SELPLG M621 G→A, methylenetetrahydrofolate reductase (MTHFR) C677T, methionine synthase reductase (MTRR) A66G, coagulation factor VII 10976 G→A. At stroke pts studied data coagulogram tests and homocysteine level before anticoagulant therapy. REsults: Total frequency of prothrombin gene G20210A, factor V Leiden, MTHFR (C677T) and MTRR (A66G) mutations at stroke pts in 2.8 times is higher, than at healthy children. The polymorphisms in homocysteine metabolism genes met more often: MTRR (66GG) in 30.6% of cases, MTHFR (677TT) in 8.3% of cases. The homocysteine level at stroke pts exceeded the upper limit of normal age level and also was significantly elevated in at carriers of these genes: 10.29±1.55 mcmol/l vs 7.33±0.6 mcmol/l (p = 0.018). In coagulogram the anticoagulant system disorders (decrease of a protein C activity – in 22.7% of cases, protein S activity – in 13.6% and antithrombin III – in 12.5% of cases), and also increase of D-dimer level – in 21% of cases are found out. Conclusions: The impact prothrombotic disorders must be examined in relation to other established risk factors and potentially new therapeutic strategies. It is reasonable to measure the serum homocysteine level at ischemic stroke pts.

Case-control Study of Methylenetetrahydrofolate Reductase Mutations and Hyperhomocysteinemia and Risk of Stroke

The association of factor V-Leiden and methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C mutations with stroke was investigated in 118 patients with stroke and 120 control subjects. MTHFR 677TT (P < .001) and 1298CC (P < .001), but not factor V-Leiden (P = .179), genotypes were associated with stroke. The C677T but not A1298C MTHFR mutation was associated with elevated homocysteine levels in patients and control subjects. In addition to hypertension, the significant predictors for stroke were MTHFR 677CT and TT and A1298CC genotypes, together with hyperhomocysteinemia, indicating a synergistic effect of MTHFR mutations with elevated homocysteine and other risk factors in pathogenesis of stroke.

Genetic Thrombophilias and Intrauterine Growth Restriction

To estimate the relationship between inherited thrombophilias and intrauterine growth restriction (IUGR) using meta-analytic techniques. A literature review identified case-control and cohort studies evaluating the relationship between IUGR and the following thrombophilias: homozygous or heterozygous factor V Leiden or prothrombin (PT) G20210A mutations and homozygous methylenetetrahydrofolate reductase (MTHFR) C677T mutation. Using mixed effects and random-effects models, the association between thrombophilias and IUGR was explored. Publication bias was assessed with funnel plots and corrected for with Duval and Tweedie's trim-and-fill method. The following number of related studies were found: studies evaluating relationships between factor V Leiden mutation and IUGR, 12 case-control and four cohort; between PT mutation and IUGR, 11 case-control and 0 cohort; and between MTHFR C677T homozygosity and IUGR, 10 case-control and two cohort. The overall summary odds ratio (OR) for the association between factor V Leiden and IUGR was significant (OR 1.23, 95% confidence interval [CI] 1.04-1.44); however, this was mainly driven by the positive association seen in the case-control studies (OR 1.91, 95% CI 1.17-3.12). The association between PT and IUGR was only explored in case-control studies yielding a summary OR that was not significant (OR 1.52, 95% CI 0.98-2.35). The overall summary OR for the association between MTHFR and IUGR was not significant (OR 1.01, 95% CI 0.88-1.17), but was significant for the case-control studies alone (OR 1.35, 95% CI 1.04-1.75). For both factor V Leiden and MTHFR mutations, a funnel-plot analysis of the case-control studies suggests publication bias. When the trim-and fill-method was used to correct for the publication bias, these summary estimates were no longer significant. The association between inherited thrombophilias and IUGR can only be discerned in case-control studies and seems to be largely because of publication bias. III.

MOLECULAR PATHOPHYSIOLOGY OF THROMBOTIC STATES AND THEIR IMPACT TO LABORATORY DIAGNOSTICS

Molecular genetic methods were implemented in the detection of thrombophilic disorders in the 1990's with the discovery of coagulation inhibitors antithrombin III (AT III), protein C (PC) and S (PS). The discovery of the molecular cause of activated protein C (APC) resistance by Bertina in 1994 greatly expanded their utilization. Currently, a broad group of molecular genetic markers with a clearly demonstrated risk of thrombophilia are used--mutation of FV Leiden 506R/Q, mutation of prothrombin (F II) 20210G/A, mutation of methylenetetrahydrofolate reductase (MTHFR) 677C/T in homozygous form, mutation of plasminogen activator inhibitor (PAI-1) 4G/5G, mutations of single coagulation inhibitors as well as a number of polymorphisms with controversial thrombophilic risk such as F XIII Val34Leu, platelet glycoproteins, endothelial protein C receptor and thrombomodulin. Another area utilizing molecular genetic methods is research of the pathophysiology of individual coagulation processes. To date, the greatest advances in regard to APC resistance have been achieved here. Although the molecular cause of APC resistance was clearly demonstrated in the 1990's, its clinical variability has not yet been fully explained. The same is true for the second most widespread mutation, prothrombin gene mutation, where only the latest research has hinted at a possible mechanism of expression of the genetic changes in the actual coagulation process. The future of molecular genetic methods is in achieving a complex understanding of the pathophysiology of thrombophilia and not only in its utilization as a method for detecting many polymorphisms with a very low risk of thrombosis.

Hereditary Thrombophilic Factors in Stroke Due to Cerebral Infarct

BackgroundThe stroke is the third most common cause of all deaths. In new studies, the importance of hereditary thrombophilic factors on stroke is emphasized. The aim of this study is to determine the role of hereditary thrombophilic factors including factor V Leiden A1691G (FVL), prothrombin G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T gene mutations in patients with stroke because of cerebral infarct. MethodsTwenty-four patients with stroke and 53 controls with risk factor for stroke were enrolled. Polymerase chain reaction was used to detect these mutations. ResultsHeterozygote FVL mutation in 2 (8.3%) patients and MTHFR mutation in 10 (41.7%) patients were detected. In the control group, there were 2 (3.8%) patients with heterozygote FVL mutation and 15 (28.3%) patients with MTHR mutation. Both FVL and MTHFR gene mutations were detected in 1 patient and 2 controls, respectively. Prothrombin gene mutation was not found in 2 groups. There were not statistically significant differences for all 3 mutations in-between 2 groups (P > 0.05). Odds ratios were 0.431 (0.074–2.504, 95% CI) for FVL mutation and 0.553 (0.221–1.381, 95% CI) for MTHFR mutation, respectively. ConclusionAlthough our study group was small, hereditary thrombophilic factors might not be risk factors for stroke because of cerebral infarct.

Oral contraceptive pills and inherited thrombophilia in a young woman with deep venous thrombosis

Inherited risk factors for vascular disease include factor V Leiden prothrombin and methylenetetrahydrofolate reductase (MTHFR) point mutations. The use of oral contraceptives is also a recognized risk factor for venous thromboembolism. In Eastern Mediterranean countries the highest frequency of factor V Leiden was reported in Lebanon (14%). However there are no studies related to awareness of the use of oral contraceptive pills among individuals with a high risk for thrombotic events. Here we present the case of a female patient on oral contraceptive pills who sustained an extensive deep venous thrombosis (DVT). The patient was found to be heterozygous for factor V Leiden (G1691A) and homozygous for the MTHFR (C677T) mutations. (excerpt)

Plasma Homocysteine, MTHFR Gene Mutation, and Open-angle Glaucoma

Elevated plasma homocysteine has been associated with an increased risk of cardiovascular disease. The association between open-angle glaucoma and cardiovascular disease has recently stimulated interest in the role of homocysteine in the pathogenesis of glaucoma. Some studies report elevated plasma homocysteine in patients with pseudoexfoliation syndrome and pseudoexfoliation glaucoma (PXFG), but have not found this association consistently in other types of open-angle glaucoma. In this study, we have measured plasma homocysteine and C677T methylenetetrahydrofolate reductase (MTHFR) mutation, the commonest genetic cause of elevated plasma homocysteine, in patients with PXFG, primary open-angle glaucoma (POAG), and normal tension glaucoma (NTG). Prospective cross-sectional cohort study. Forty-eight patients with PXFG, 36 patients with POAG, 34 patients with NTG, and 42 controls without glaucoma. Fasting venous blood samples from each participant were analyzed for plasma homocysteine and the C677T MTHFR gene mutation. MAIN OUTCOME OF INTEREST: Mean plasma homocysteine levels, number of individuals with homocysteine above the reference range, and percentage of individuals with heterozygous or homozygous C677T MTHFR gene mutations. Mean plasma homocysteine was significantly higher in PXFG (11.77+/-4.18 micromol/L), POAG (11.21+/-2.84 micromol/L), and NTG (11.74+/-3.79 micromol/L) compared with control (9.82+/-1.75 micromol/L). Hyperhomocysteinemia was found in 27.1% of PXFG patients, 30.6% of POAG patients, and 29.4% of NTG patients. There was no significant difference in frequency of MTHFR C677T gene mutation between groups. Plasma homocysteine was elevated in PXFG, POAG, and NTG. Elevated plasma homocysteine seems to be associated with glaucoma in these patients.

Methylene Tetrahydrofolate Reductase and Angiotensin Converting Enzyme Gene Polymorphisms Related to Overweight/Obesity among Saudi Subjects from Qassim Region

Background: This work was planned to check for the association of polymorphisms related to methylenetetrahydrofolate reductase (MTHFR) and angiotensin converting enzyme (ACE) genes with overweight/obesity among Saudi subjects from Qassim region.Methods: This work included 130 subjects having overweight or obesity and 111 normal controls. Their age mean ± SD was 27 ± 9.8 and 24 ± 8.8 years respectively. Their DNA was analyzed for polymorphisms of MTHFR; 677C/T and 1298 A/C and ACE; I/D genes using real-time PCR.Results: Genotype and allele frequencies of studied polymorphisms in cases of overweight/obesity showed no significant statistical difference compared to that of controls. However, on analysis of body mass index (BMI), cases showed slightly higher but statistically nonsignificant mean ± SD values among those carrying the mutant MTHFR 677 T allele (CT + TT vs. CC, 30.7 ± 4.5 vs. 29.9 ± 4.9), 1298 C allele (AC + CC vs. AA, 29.9 ± 4.1 vs. 29.7 ± 5.5) and ACE D allele (ID + DD vs. II, 30.0 ± 5.1 vs. 29.1 ± 2.8). In addition controls having the DD and ID genotypes showed higher statistically significant values of BMI than those of the II genotype (22.0 ± 1.9, 21.7 ± 2.6 and 19.5 ± 2.3 respectively,p&lt; 0.05).Conclusion: There is no solid association of polymorphisms related to MTHFR and ACE genes with non-complicated overweight or obesity among Saudi subjects from Qassim Region.

Methylene tetrahydrofolate reductase and angiotensin converting enzyme gene polymorphisms related to overweight/obesity among Saudi subjects from Qassim Region.

Background: This work was planned to check for the association of polymorphisms related to methylenetetrahydrofolate reductase (MTHFR) and angiotensin converting enzyme (ACE) genes with overweight/obesity among Saudi subjects from Qassim region. Methods: This work included 130 subjects having overweight or obesity and 111 normal controls. Their age mean ± SD was 27 ± 9.8 and 24 ± 8.8 years respectively. Their DNA was analyzed for polymorphisms of MTHFR; 677C/T and 1298 A/C and ACE; I/D genes using real-time PCR. Results: Genotype and allele frequencies of studied polymorphisms in cases of overweight/obesity showed no significant statistical difference compared to that of controls. However, on analysis of body mass index (BMI), cases showed slightly higher but statistically nonsignificant mean ± SD values among those carrying the mutant MTHFR 677 T allele (CT + TT vs. CC, 30.7 ± 4.5 vs. 29.9 ± 4.9), 1298 C allele (AC + CC vs. AA, 29.9 ± 4.1 vs. 29.7 ± 5.5) and ACE D allele (ID + DD vs. II, 30.0 ± 5.1 vs. 29.1 ± 2.8). In addition controls having the DD and ID genotypes showed higher statistically significant values of BMI than those of the II genotype (22.0 ± 1.9, 21.7 ± 2.6 and 19.5 ± 2.3 respectively, p < 0.05). Conclusion: There is no solid association of polymorphisms related to MTHFR and ACE genes with non-complicated overweight or obesity among Saudi subjects from Qassim Region.

Hemolysis and hyperhomocysteinemia caused by cobalamin deficiency: three case reports and review of the literature

Concurrent hemolysis in patients with vitamin B12 deficiency is a well-recognized phenomenon and has been attributed to intramedullary destruction of erythrocytes (ineffective erythropoiesis). Recent studies revealed that homocysteine increased the risk of hemolysis in vitamin B12 deficiency in vitro and there is a high frequency (30%) of vitamin B12 deficiency in asymptomatic patients with homozygous methylene tetrahydrofolate reductase (MTHFR) C677T mutation, a known cause of hyperhomocysteinemia. Here we report three patients with MTHFR mutations and vitamin B12 deficiency presenting with hemolytic anemia and severely elevated homocysteine levels. Patients demonstrated complete resolution of hemolysis with simultaneous normalization of serum homocysteine levels after vitamin B12 treatments. We reviewed pertinent literature, and hypothesized that hemolytic anemia may be more prevalent in patients who have a coexisting MTHFR gene mutation and vitamin B12 deficiency possibly related to severely elevated homocysteine levels. The hemolysis in these cases occurred predominantly in peripheral blood likely due to the combined effects of structurally defective erythrocytes and homocysteine-induced endothelial damage with microangiopathy.

A High Incidence of Patients with MTHFR (methylenetetrahydrofolate reductase) Gene Mutations Noted in An Appalachian Population Seen for Thrombophilia at the West Virginia University Outpatient Hematology Clinic, 2006–2008

Background: One or more risk factors for deep vein thrombosis (DVT) and pulmonary embolism (PE), either hereditary or acquired, can be identified in up to 80% of patients with venous thromboembolism (VTE). Some patients have more than one form of inherited thrombophilia and appear to be at greater risk for thrombosis. We noted a higher than expected incidence of MTHFR gene mutations C677T or A1298C in Appalachian patients referred to our benign hematology clinic. Studies have suggested an increased risk of venous thromboembolism (VTE) in patients with hyperhomocysteinemia, and the C677T mutation in the MTHFR gene has been thought responsible for hyperhomocysteinemia. However, the association of MTHFR gene mutations C677T and A1298C and VTE remains controversial.Methods: We reviewed the records of 72 patients for risk factors for acquired or inherited thrombophilia. These patients were referred to our benign hematology clinic for thrombophilia evaluation between 2006 and 2008. All available medical history for risk factors and laboratory test results, obtained from first VTE through time of consultation, including genetic testing, were reviewed. Anti-cardiolipin antibody (ACA), MTHFR genotyping and Protein C and Protein S assays were performed at Warde Medical Laboratory, Ann Arbor, MI.Results: 72 patients were seen from 2006–2008. Of these, 45 patients (63%) had established VTE per ATS clinical practice guidelines and are the subject of this report. Excluded patients had stroke only (CVA) without other VTE, or were screened for thrombophilia based of family history or prior fetal loss. Of the 45 patients with established VTE, median age at first clot was 34 years (range 14–65) and median age at consultation was 41 years (range 19–72). There were 21 men and 24 women (47% and: 53%). Recorded sites of VTE were legs (54 events), arms (8 events), pulmonary embolism (22 events) and stroke with VTE (3 events). Review of risk factors showed that 90 % of the patients had good performance status (NCI 0,1); 47% were obese with BMI > 30 (median BMI was 29.6); 47% were smokers; 49 % had a positive family history of VTE; 42 % had dyslipidemia; 9% had cancer (3 prior, 1 active germ cell testis tumor); and 16% used oral contraceptives or hormones. 33 of the 45 VTE patients had homocysteine levels available, and the median homocysteine level was 10 micromol/L (range 5.8 –63); 7 (21%) had an elevated homocysteine level, greater than 14. 32 of the 45 VTE patients had MTHFR gene mutation testing done, and 28 of the 32 (88 %) had one or more positive mutations, with alleles C677TT (10%-high risk), C677T (68%), A1298CC (14%), A1298C (39%). Further, 9 of the 32 patients (32%) and the “high risk” C677T-A1298C mutation. Thus, 42% of all patients tested had a “high risk” MTHFR gene mutation for VTE.Coagulation Profile of 45 Thrombophilia Clinic Patients with established VTE# tests (+)# tests done%Anti-Cardiolipin Antibody53613Anti-Thrombin III2366Factor II 20210 Gene Mutation2406Factor V Leiden Gene Mutation104025Lupus Anti-coagulant2316.4xMTHFR Gene Mutation283288Protein C2307Protein S32910Conclusion: Patients with established VTE in our clinic population inherited risk factors as tabulated above. The Factor II and Factor V mutation incidences of 6% and 25%, as well as the number of abnormalities in Protein C, Protein S, and Anti-Cardiolipin Antibody, appear similar to data reported in the literature for Caucasian populations. However, Rodrigues et al reported a C677TT and C677T prevalence of 14–19% and 36–47% respectively in 1,277 normal persons and a A1298 CC and A1298C prevalence of 7–11 % and 28–35 % respectively (Am J Clin Nutr 2006; 83:701).,. In our Appalachian population, the overall incidence of MTHFR genetic mutations (88 %) and the number of “high risk” MTHFR mutations (42%) appears excessive and deserves further investigation.

Effect of methylenetetrahydrofolate reductase and thymidylate synthase enhancer region polymorphisms on the risk of idiopathic recurrent spontaneous abortion in a Korean population

Previous studies reported an association of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and recurrent spontaneous abortion, whereas no studies are available for the association with thymidylate synthase enhancer region (TSER) genotypes. Mutations of MTHFR and TSER are not likely significant risk factors of idiopathic recurrent spontaneous abortion in Korean women.

Repeated in vitro Fertilization Failure and Its Relation with Thrombophilia

Background: The objective of this study was to determine the prevalence of some thrombophilic factors and its relation to in vitro fertilization (IVF)-embryo transfer failure in women who had had three or more previously failed IVF-embryo transfer cycles. Methods: The study group included 51 consecutive women with three or more previously failed IVF-embryo transfer cycles (group 1). The control group included 50 women who conceived spontaneously with at least one uneventful pregnancy and no previous history of miscarriage. All women were tested for the presence of factor V Leiden, prothrombin (G20210A), and methylenetetrahydrofolate reductase (C677T) mutations. Results: A similar prevalence of factor V Leiden, prothrombin, and methylenetetrahydrofolate reductase mutations was found in both groups. At least one inherited thrombophilic factor was detected in 62.7% of women with repeated IVF failure and in 53.9% of women in group 2. No association between repeated IVF failure and these thrombophilic factors was found statistically. Conclusion: These data suggest that factor V Leiden, methylenetetrahydrofolate reductase and prothrombin gene mutation do not have a significant role in IVF-embryo transfer implantation failure.

Drug Related Genetic Polymorphisms Affecting Adverse Reactions to Methotrexate, Vinblastine, Doxorubicin and Cisplatin in Patients With Urothelial Cancer

There is considerable interindividual diversity in the development of adverse reactions during chemotherapy for cancers. This diversity is suggested to be attributable to differences in the disposition of chemotherapeutic agents, which is modified by genetic polymorphisms. In this study we evaluated the possible association of polymorphisms of genes involved in the metabolism, detoxification and transport of the agents with adverse reactions to methotrexate, vinblastine, doxorubicin and cisplatin therapy. A total of 40 patients with urothelial cancer who received methotrexate, vinblastine, doxorubicin and cisplatin or high dose methotrexate, vinblastine, doxorubicin and cisplatin chemotherapy between 1996 and 2005 at Akita University Medical Center were included in this study. Four genetic polymorphisms (ABCB1, GSTP1, CYP3A5 and MTHFR) and clinical parameters were included in the analysis to determine whether there was any association with the grade of adverse reactions at the first cycle and the worst grade of each adverse reaction throughout the chemotherapy period. On multivariate analysis the CYP3A5 A6986G genotype *3/*3 (OR 8.205, 95% CI 1.616-41.667, p = 0.011) and smaller number of treatment cycles (OR 0.156, 95% CI 0.037-0.659, p = 0.011) were independent factors for leukocytopenia (grade 3 or greater) throughout the period of chemotherapy. The mean white blood cell count nadir in patients with genotype *3/*3 was significantly lower than that in those with the *1 allele (1,542 +/- 903 vs 2,431 +/- 973/mm(3), p = 0.009). The A6986G polymorphism of CYP3A5, which is involved in the metabolism of vinblastine and doxorubicin, might be a genetic predictor of the severity of leukocytopenia induced by chemotherapy with methotrexate, vinblastine, doxorubicin and cisplatin.