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BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) has become a major public health problem all over the world. After the 2019 coronavirus illness (COVID-19), the pandemic may have influenced research priorities and resource allocation, potentially affecting the ability to monitor MRSA trends. AIMS: The study aimed to evaluate the prevalence of S. aureus, including MRSA infections, and their antimicrobial susceptibilities over the years 2019 and 2020 in a tertiary hospital in Makkah City, KSA. METHODOLOGY: A total of 2128 and 1515 laboratory (lab) samples were collected during the years 2019 and 2020, respectively. From these samples, the prevalence of S. aureus, including MRSA, and their antibiotic susceptibility were identified using standard, automated, and molecular microbiological methods. RESULTS: The present study shows that the lab prevalence of all S. aureus during 2019 was found to be 35.5%, of which MRSA was 44.8%. During 2020, the frequency of S. aureus strains was 16%, of which MRSA was 41.2%. The most common MRSA isolated during both years were colonizing pus swabs and urine samples. The results showed that MRSA susceptibility against antimicrobial agents in 2019 was as follows: vancomycin (100%), linezolid (100%), trimethoprim-sulfamethoxazole (88%), and doxycycline (34.2%). The MRSA strains isolated during 2020 were as follows: vancomycin (100%), linezolid (96%), trimethoprim-sulfamethoxazole (100%), and doxycycline (24.3%). There was no significant difference in the incidence and antimicrobial resistance rates of MRSA over the two years. CONCLUSION: It was concluded that the prevalence rates of MRSA have not increased in 2020 when compared to 2019. Vancomycin, linezolid, trimethoprim-sulfamethoxazole, and doxycycline remain susceptible to the positive collected MRSA strains. There was no significant difference between the prevalence and antimicrobial resistance rates of MRSA between 2019 and 2020. Continued research efforts are needed to address this persistent public health threat. Strategies to control the spread of MRSA should include early detection of MRSA and surveillance, even during pandemics.
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[This corrects the article DOI: 10.1155/2023/6608279.].
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BACKGROUND: Testing of blood donors for markers of transfusion-transmitted infections (TTIs) such as HBV, HCV, HIV, HTLV, syphilis, and malaria is mandatory in Saudi Arabia. This study determined the prevalence of all tested TTIs among blood donors in the western region of Saudi Arabia. METHODS: This retrospective study included 5,473 blood donors who attended the blood donation center at the Security Force Hospital (SFH) located in the western region of Saudi Arabia from January 1, 2015 to December 31, 2018. The prevalence of TTIs was determined and classified as per year, gender, age, type of donors (first-time vs. returned donors), category of donation (replacement vs. volunteer), and blood group. RESULTS: All donors (100%) were screened for TTIs by serological assays and nucleic acid tests (NATs). "Reactive" samples to serological assays were as follow: 57 (1.07%) HBsAg, 292 (5.34%) HBsAb, 388 (7.1%) HBcAbs, 13 (0.24%) HCV, 5 (0.09%) HIV, 8 (0.15%) HTLV-I and -II, 21 (0.83%) syphilis, and 0 (0%) malaria. The NAT results for HBV, HCV, and HIV revealed 50 (0.91%), 1 (0.0002%), and 3 (0.05%) reactive samples, respectively. Reactive donations to screening serology tests of syphilis and HTLV-I/-II were neither confirmed nor declined by their corresponding confirmatory assays. Most "reactive" samples to TTI tests were associated with male gender, first-time donor, replacement donation, and O+ blood group. CONCLUSIONS: This study highlights the strong adherence to TTI testing policy and low prevalence of TTI markers among blood donors in the western region of Saudi Arabia.
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Antígenos de Grupos Sanguíneos , Infecciones por VIH , Hepatitis C , Sífilis , Reacción a la Transfusión , Humanos , Masculino , Donantes de Sangre , Sífilis/diagnóstico , Sífilis/epidemiología , Prevalencia , Estudios Retrospectivos , Arabia Saudita/epidemiología , Reacción a la Transfusión/epidemiología , Hospitales , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Hepatitis C/diagnóstico , Hepatitis C/epidemiologíaRESUMEN
Methods: We report the case of a 73-year-old Saudi female who presented with severe thrombocytopenia and mild autoimmune hemolytic anemia associated with brucellosis. The coexistence of published cases of two hematological disorders with brucellosis is rare. Results: Despite the initial treatment with eltrombopag and intravenous immunoglobulin (IVIG), our patient's platelets count remained low and significantly improved after initiation of brucellosis treatment in the form of rifampicin and doxycycline. Discussion. We conclude by reviewing the case that in many parts of Saudi Arabia, brucellosis remains a prevalent infection. Hence, it should be considered as a possible diagnosis in febrile individuals with no localizing indications and the presence of severe thrombocytopenia in acute febrile illness. Although it is a rare association, it could be related to brucellosis. Conclusion: This is our region's first published case of severe thrombocytopenia and mild autoimmune hemolytic anemia associated with brucellosis. It contributes to the literature on the successful use of rifampicin and doxycycline to treat hematological disorders associated with brucellosis.
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Objectives: This study aims to investigate hemostatic changes in patients with coronavirus disease (COVID-19) and their relationship to disease severity and survival. Methods: This study included 284 patients with COVID-19 who attended the Security Forces Hospital, Makkah, Saudi Arabia between October 2020 and March 2021, and retrospectively reviewed their demographic, radiological, and laboratory findings. The coagulation profile was assayed at the time of diagnosis for platelet counts using an automated hematology analyzer; Sysmex XN2000 while international normalized ratio (INR), activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, factor VIII, ristocetin cofactor (RiCoF), and von Willebrand factor antigen (VWF-Ag) were measured by Stago kits on a Stago automated coagulation analyzer (STA Compact Max®). Results: In this study, 32.3% of the cases had severe disease, while 8.8% of the cases died. D-dimer, factor VIII, and RiCoF were the only independent predictors of disease severity, with factor VIII and RiCoF having significantly higher areas under the curve (AUCs) than D-dimer (all p < 0.001). Furthermore, age, aPTT, and factor VIII were associated with an increased risk of mortality in multivariate Cox regression analysis, with factor VIII having a higher AUC of 0.98 than aPTT with an optimal cut-off value of >314 IU/dl in predicting mortality. Cases with factor VIII levels >314 IU/dl, compared to those with factor VIII levels <314 IU/dl, were associated with a significantly shorter mean overall survival time (20.08 vs. 31.35 days, p < 0.001), a lower survival rate (30.3% vs. 99.2%, p < 0.001), and a 16.62-fold increased mortality risk. Conclusion: RiCoF is a novel predictor of disease severity in COVID-19, while factor VIII is confirmed as a predictor of severity and mortality in COVID-19 patients and is associated with lower overall survival and increased mortality risk.
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Factores de Coagulación Sanguínea , COVID-19 , Factores de Coagulación Sanguínea/análisis , COVID-19/diagnóstico , COVID-19/mortalidad , Factor VIII/análisis , Humanos , Estudios Retrospectivos , Arabia Saudita/epidemiología , Índice de Severidad de la Enfermedad , Factor de von Willebrand/análisisRESUMEN
This study was designed to evaluate the effect of Methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms on MTX toxicity in pediatric Egyptian ALL patients. Ninety-Four of Pediatric ALL patients aged 3-13 years (7.6 ± 3.6) on oral maintenance dose of 50 mg/m2 weekly of MTX. MTHFR c.677C>T (rs1801133) and c.1298A>C (rs1801131) genotyping were performed using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The allele frequencies of c.677C>T were 42.6%, 46.8%, and 10.6% for CC, CT, and TT respectively, while c.1298A>C alleles frequencies were 62.7%, 24.5%, and 12.8% for AA, AC, and CC respectively. None of the investigated polymorphism (C677T or A1298C alleles) was associated with either overall or site specific MTX toxicity regarding anemia (p = 0.99) (p = 0.4), platelets (p = 0.4) (p = 0.4), hepatotoxicity (p = 0.4) (p = 0.7), respectively. The results indicated that between c.677C>T genotypes, CC/CT and TT were associated with hematopoietic toxicities 60.7% and 60% (p = 0.2); platelet toxicities 76.2% and 80% (p = 1) and, hepatotoxicities 40.5% and 60% (p = 0.3), respectively. In the c.1298A>C genotypes, CC/AC and AA presented hematopoietic toxicities 68.6% and 55.9% (p = 0.2), platelet toxicities 82.9% 72.9% (p = 0.3) and, hepatotoxicity 37.1% and 45.8% (p = 0.5), respectively. No significant associations were detected between MTHFR c.677C>T or c.1298A>C polymorphisms and either overall or site specific MTX toxicity.
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BACKGROUND: Genotypic mutation of fms like tyrosine kinase 3 (FLT3), Nucleophosmin (NPM1), and DNA-methyltransferase 3A (DNMT3A) has been involved in the leukemogenesis of acute myeloid leukemia (AML), with the well known poor prognostic role of FLT3 and DNMT3A and favorable role for the NPM1 mutation. PATIENTS AND METHODS: A total of 123 patients with AML treated at the National Cancer Institute, Cairo University were examined for mutations in DNMT3A, FLT3, and NPM1 using polymerase chain reaction (PCR) for detecting FLT3 internal tandem duplication (ITD) and allele-specific PCR to detect DNMT3A and NPM1A mutations. Two-way direct sequencing and Gene Mapper version 4.0 software (Fred Hutchinson Cancer Research Center) sequencing were used as confirmatory tests for DNMT3A and NPM1A mutations, respectively. RESULTS: DNMT3A, FLT3-ITD, and NPM1A gene mutations were detected in 22 (17.9%), 22 (17.9%), and 24 (19.5%) patients, respectively. DNMT3A/FLT3, NPM1A/FLT3, and DNMT3A/NPM1A combined mutant genotypes were detected in 5 (4.1%), 9 (7.3%), and 3 (2.4%) patients, respectively. Two patients (1.6%) had triple mutant genotypes (DNMT3A/FLT3/NPM1A). FLT3 and DNMT3A mutations had a significant negative effect on complete response (CR) rates (P = .016). FLT3-ITD mutation was significantly associated with older age (P = .029), and lower overall survival (OS) rates (P = .046). DNMT3A/FLT3 combined mutant genotypes were significantly associated with a lower OS rate (P = .016). Mutant NPM1/wild type FLT3, wild type DNMT3A/FLT3, and mutant NPM1A/wild type DNMT3A combinations were significantly associated with higher CR rates (P = .006, P = .006, and P = .023, respectively). CONCLUSION: DNMT3A, FLT3-ITD, and NPM1A are frequent mutations in Egyptian AML. FLT3-ITD mutations are frequent in older patients. DNMT3A and FLT3-ITD mutations were associated with an unfavorable prognosis, but the NPM1A mutation has tendency to indicate a good prognosis.
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ADN (Citosina-5-)-Metiltransferasas/genética , Duplicación de Gen , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/mortalidad , Mutación , Proteínas Nucleares/genética , Tirosina Quinasa 3 Similar a fms/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Niño , Preescolar , ADN Metiltransferasa 3A , Egipto , Femenino , Humanos , Lactante , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Tasa de Mutación , Nucleofosmina , Fenotipo , Pronóstico , Análisis de Supervivencia , Adulto JovenRESUMEN
Graft-versus-host disease (GVHD) is the major complication of allogeneic hematopoietic stem cell transplantation (HSCT); cytokines are recognized as important mediators in its pathogenesis. In this study we investigated the role of cytokine gene polymorphisms on HSCT outcome. A total of 106 patient and 98 donors were genotyped by polymerase chain reaction sequence specific primers (PCR-SSP) based assay for tumor necrosis factor-α-308 (TNFα -308), interleukin (IL)-6-174, IL-10-1082, -819, -592, Interferon-γ+874 (IFN-γ+874), and transforming growth factor-ß1 (TGF-ß1) codon10 and 25 polymorphisms. Except one in each category, all patients and donors were TNFα -308 high producers and the majority were IL-6-174 high producers (93.3% and 90.8% respectively); a pattern that would alleviate any potential biological impact. Patient's IFN-γ+874 showed significant association with the development of chronic GVHD. Patients with IFN-γ +874 high producer showed an 8 folds likelihood to develop chronic GVHD as compared to those with IFN-γ+874 low producer predicted phenotype (95% CI: 1.59-40.2, pâ¯=â¯0.01). Patient's TGFß1-codon 10 and 25 high/intermediate producers showed a lower incidence of acute GVHD though it did not achieve statistical significance (pâ¯=â¯0.065) on account of the low frequency of this genotype in our patients and donors (11.4 and 8.2% respectively). Other factors contributing to risk of GVHD included older age for both acute and chronic (pâ¯=â¯0.01 and 0.02 respectively) with age 24 as the best discriminating cutoff; CD34+ cell dose for chronic GVHD (pâ¯=â¯0.045) with a dose of 8â¯×â¯106/kg as the best discriminating cutoff; and conditioning regimen with Flu/Bu associated with the lowest incidence of acute GVHD (pâ¯=â¯0.003) and no impact on chronic GVHD. In conclusion the current study further indicates a potential role of some cytokine gene polymorphisms in the development of GVHD. The relative distribution of high and low producer genotypes in different ethnic groups contributes to their biological impact in different populations.
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Citocinas/genética , Antígenos HLA/genética , Polimorfismo de Nucleótido Simple/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Genotipo , Enfermedad Injerto contra Huésped/genética , Enfermedad Injerto contra Huésped/prevención & control , Trasplante de Células Madre Hematopoyéticas/métodos , Humanos , Masculino , Persona de Mediana Edad , Fenotipo , Hermanos , Trasplante Homólogo/métodos , Adulto JovenRESUMEN
BACKGROUND AND OBJECTIVES: Detection of chromosomal abnormalities in myeloproliferative disorders is important for proper diagnosis of these disorders. This study has investigated the presence of JAK2 mutation (V617F) in Egyptian patients with myeloproliferative disorders referred to National Cancer institute, Cairo University. METHODS: The study involved 110 cases of Philadelphia negative Myeloproliferative diseases (MPDs), 70 cases with Polycythemia Vera (PV), 24 cases with Essential Thrombocytosis (ET) and 16 cases with Idiopathic Myelofibrosis (IMF) and 20 cases as a control group which represented as; (10 cases with secondary erythrocytosis, 1 case with reactive thrombocytosis, 4 cases as normal control and 5 as Philadelphia positive Chronic Myeloid Leukemia cases), they were collected from National Cancer Institute (NCI) over 3 years. We used ARMS technique for mutation detection. RESULTS: The frequency of the V617F JAK2 mutation was highest in patients with PV where 56 out of 70 cases (80%) carried the mutation, followed by ET with 6 of 24 (25) and IMF with 2 of 16 (12.5%) . None of the cases with secondary Erythrocytosis, reactive thrombocytosis, the normal controls or Philadelphia positive CML cases carried the mutation. CONCLUSIONS: Our results are concordant with international published results for detection of this mutation. It is unequivocal now that V617F is met in many MPDs especially PRV. Finding this mutation in those patients is thought to have a big impact on the diagnosis and treatment of these disorders.
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Janus Quinasa 2/genética , Trastornos Mieloproliferativos/genética , Adulto , Anciano , Sustitución de Aminoácidos , Egipto , Femenino , Frecuencia de los Genes , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Masculino , Persona de Mediana Edad , Mutación , Policitemia Vera/genética , Prevalencia , Mielofibrosis Primaria/genética , Trombocitosis/genéticaRESUMEN
N-Acetyltransferases (NAT) have been known to modify the risk to a variety of solid tumors. However, the role of NAT2 polymorphism in risk susceptibility to childhood acute lymphoblastic leukemia (ALL) is still not well known. We performed a case-control study to determine if the common NAT2 polymorphisms play a role in altering susceptibility to pediatric ALL. DNA of 92 pediatric ALL patients and 312 healthy controls was analyzed for the NAT2 polymorphisms using the PCR-RFLP method. The wild-type NAT2*4 was encountered in 8.6 % of patients versus 11.8 % of controls (P = 0.23). The rapid acetylators NAT2*12 803A>G, AG, GG, and AG/GG were overrepresented in controls (P = 0.0001; odds ratio (OR) 0.22, 0.19, and 0.21 respectively). NAT2*5D 341T>C and NAT2*11A 481C>T were of comparable frequencies. For their combination, NAT2*5A, a slow acetylator, both TCTT and CCCT were overrepresented in patients (P < 0.001; OR 15.8 and 17.9 respectively). NAT2*5B (803A>G, 341T>C, 481C>T) was overrepresented in controls (P < 0.001; OR 0.12). Apparently, 803A>G ameliorated the combined effect of 341T>C and 481C>T. A similar effect was obtained with NAT2*5C (341T>A, 803A>G) (P < 0.0001; OR 0.11). For slow acetylator NAT2*7A 857G>A, GA and GA/AA were overrepresented in patients (P = 0.009 and 0.01; OR 2.74 and 2.72 respectively). NAT2*13 282C>T, NAT2*6B 590G>A, and NAT2*14A 191G>A were of comparable frequencies. NAT2 282C>A in combination with NAT2 857G>A (NAT2*7B) showed a synergistic effect in patients versus controls (P < 0.0001; OR 3.51). In conclusion, NAT2 gene polymorphism(s) with slow acetylator phenotype is generally associated with the risk of development of ALL in children.
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Arilamina N-Acetiltransferasa/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Acetilación , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Genotipo , Humanos , Lactante , Masculino , Polimorfismo de Nucleótido Simple , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología , Factores de RiesgoRESUMEN
BACKGROUND: The P53 tumor suppressor gene plays a pivotal role in maintaining cellular homeostasis by preventing the propagation of genome mutations. P53 in its transcriptionally active form is capable of activating distinct target genes that contribute to either apoptosis or growth arrest, like P21. However, the MDM2 gene is a major negative regulator of P53. Single nucleotide polymorphisms (SNP) in codon Arg72Pro of P53 results in impairment of the tumor suppressor activity of the gene. A similar effect is caused by a SNP in codon 31 of P21. In contrast, a SNP in position 309 of MDM2 results in increased expression due to substitution of thymine by guanine. All three polymorphisms have been associated with increased risk of tumorigenesis. AIM OF THE STUDY: We aimed to study the prevalence of SNPs in the P53 pathway involving the three genes, P53, P21 and MDM2, among acute myeloid leukemia (AML) patients and to compare it to apparently normal healthy controls for assessment of impact on risk. RESULTS: We found that the P21 ser31arg heterozygous polymorphism increases the risk of AML (P value=0.017, OR=2.946, 95% CI=1.216-7.134). Although the MDM2 309G allele was itself without affect, it showed a synergistic effect with P21 ser/arg polymorphism (P value=0.003, OR= 6.807, 95% CI= 1.909-24.629). However, the MDM2 309T allele abolish risk effect of the P21 polymorphic allele (P value= 0.71). There is no significant association of P53 arg72pro polymorphism on the risk of AML. CONCLUSION: We suggest that SNPs in the P53 pathway, especially the P21 ser31arg polymorphism and combined polymorphisms especially the P21/ MDM2 might be genetic susceptibility factors in the pathogenesis of AML.
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Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Leucemia Mieloide Aguda/genética , Polimorfismo de Nucleótido Simple , Proteínas Proto-Oncogénicas c-mdm2/genética , Proteína p53 Supresora de Tumor/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Niño , Preescolar , Intervalos de Confianza , Femenino , Predisposición Genética a la Enfermedad , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Factores de Riesgo , Transducción de Señal/genética , Adulto JovenRESUMEN
Acute lymphoblastic leukemia is the major pediatric cancer in developed countries. To date most association studies of acute lymphoblastic leukemia have been based on the candidate gene approach and have evaluated a restricted number of polymorphisms. Such studies have served to highlight difficulties in conducting statistically and methodologically rigorous investigations into acute lymphoblastic leukemia risk. Recent genome-wide association studies of childhood acute lymphoblastic leukemia have provided robust evidence that common variation at four genetic loci confers a modest increase in risk. The accumulated experience to date and relative lack of success of initial efforts to identify novel acute lymphoblastic leukemia predisposition loci emphasize the need for alternative study designs and methods. The International Childhood Acute Lymphoblastic Leukaemia Genetics Consortium includes 12 research groups in Europe, Asia, the Middle East and the Americas engaged in studying the genetics of acute lymphoblastic leukemia. The initial goal of this consortium is to identify and characterize low-penetrance susceptibility variants for acute lymphoblastic leukemia through association-based analyses. Efforts to develop genome-wide association studies of acute lymphoblastic leukemia, in terms of both sample size and single nucleotide polymorphism coverage, and to increase the number of single nucleotide polymorphisms taken forward to large-scale replication should lead to the identification of additional novel risk variants for acute lymphoblastic leukemia. Ethnic differences in the risk of acute lymphoblastic leukemia are well recognized and thus in assessing the interplay between inherited and non-genetic risk factors, analyses using different population cohorts with different incidence rates are likely to be highly informative. Given that the frequency of many acute lymphoblastic leukemia subgroups is small, identifying differential effects will realistically only be possible through multi-center pooled analyses. Here, we review the rationale for identifying genetic risk variants for acute lymphoblastic leukemia and our proposed strategy for establishing the International Childhood Acute Lymphoblastic Leukaemia Genetics Consortium.
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Predisposición Genética a la Enfermedad , Cooperación Internacional , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Alelos , Niño , Perfilación de la Expresión Génica , Regulación Leucémica de la Expresión Génica , Humanos , Polimorfismo Genético , Investigación/normas , Investigación/tendenciasRESUMEN
BACKGROUND AND PURPOSE: ALL is the most common pediatric cancer. The causes of the majority of pediatric acute leukemia are unknown and are likely to involve an interaction between genetic and environmental factors. Therefore, unfavourable gene-environmental interactions might be involved in the genesis of ALL. The aim of this work was to evaluate, in a case-control study, whether the common polymorphisms in 5, 10-methylenetetrahydrofolate reductase (MTHFR) namely (C677T and A1298C) and methionine synthase (MS) (A2756G) genes may play a role in altering susceptibility to pediatric ALL as individual genes and in combination. PATIENTS AND METHODS: DNA of 88 ALL patients (age < or = 18 years) and 311 healthy control subjects was analyzed for the polymorphisms of MTHFR and MS genes using PCR-RFLP method. RESULTS: The frequencies of the wild types of MTHFR 677CC, MTHFR 1298AA and MS 2756AA, the homozygous genotypes of MTHFR 677TT, MTHFR 1298CC and MS 2756GG and heterozygous genotypes of MTHFR 677CT and MS 2756AG showed no statistically significant differences between patients and controls. The frequency of the MTHFR 1298AC heterozygous genotype was 25% among patients compared to 45.0% among controls; the difference was found to be statistically significant (p value =0.001, O.R=0.382 & 95% C.I=0.222-0.658). The frequency of the MTHFR1298AC heterozygous genotype plus 1298CC homozygous genotype was 34% among patients compared to 54.3% among controls and the difference was statistically significant (p value =0.001). A synergistic effect of 677CT and1298AC (CTAC) was observed, (p value=0.002) with 3.65 fold protection (OR 0.273 & 95% C.I=0.155-0.9) compared to 2.6 folds for MTHFR 1298AC alone. This protective effect of CTAC polymorphism was abolished when combined with MS 2756AA or AG. CONCLUSION: The present study provided further evidence for the protective role of MTHFR 1298AC mutant alleles in acute lymphoblastic leukemia in children (2.6 fold protection). This suggests that folate and methionine metabolism play an important role in the pathogenesis of pediatric ALL. In contrast to the main bulk of literature, we did not find any protective role of either MTHFR C677T or MS A2756G polymorphisms. This may reflect the ethnic variation in both the polymorphism frequencies, variation in plasma level of folate, in addition to the possible role of gene-environment interaction mainly dietary availability of folate. The synergistic effect of MTHFR 1298AC and 677CT and its abolishment by MS 2756AA or AG further emphasizes that the interaction of genes, rather than the polymorphism in any single one, determines risk susceptibility to disease.