CRISPR/Cas9 Edition of the Gene in Human Mesenchymal Stem Cells for Hemophilia B Therapy.

Hemophilia B is a genetic disorder characterized by clotting factor IX deficiency and bleeding in joints and muscles. Current treatments involve intravenous infusion of plasma-derived products or recombinant proteins, which have limited efficacy due to the short half-life of infused proteins. Recently, gene therapy for bleeding disorders has offered a potential solution.

Inverse Shifting-PCR Modified by Capillary Electrophoresis for Detecting F8 and Inversions in Severe Hemophilia A Patients and Probable Carriers.

Globally, intron 22 inversions (Inv22s) of the factor VIII gene (F8) are the most frequent pathogenic variants and account for 45-50% of severe hemophilia A (SHA) cases, while intron 1 inversion (Inv1) explains 1-5% of SHA cases. The detection of both inversions by an inverse shifting-polymerase chain reaction (IS-PCR) is the first choice worldwide for the diagnosis of patients and carriers of SHA. To improve its sensitivity and reproducibility in the visualization of PCR products, we approached the IS-PCR with fluorescent capillary electrophoresis instead of agarose electrophoresis.

Genetic analysis for carrier diagnosis in hemophilia A and B in the Mexican population: 25 years of experience.

Our 25 years of experience in carrier diagnosis of hemophilia A (HA) and B (HB) in Mexican population comprises linkage analysis of intragenic F8/F9 neutral variants along with, in severe HA (SHA), detection of F8 int22h and int1h inversions. In symptomatic carriers (SCs) we explored Lyonization to explain their symtomatology. From a DNA-Bank of 3,000 samples, intragenic restriction fragment length (RFLPs) and short tandem repeats (STRs) of F8/F9 genes were assessed by PCR-PAGE and GeneScan.

Coronavirus Disease 2019: Hematological Anomalies and Antithrombotic Therapy.

After the first cases of COVID-19 appeared in Wuhan, China at the end of 2019, the disease quickly become a pandemic that has seriously affected the economic and health systems in more than 200 countries and territories around the world. Although most patients have mild symptoms or are even asymptomatic, there are patients who can develop serious complications such as acute respiratory distress syndrome or venous thromboembolism requiring mechanical ventilation and intensive care. Hence, it is important to identify patients with a higher risk of complications in a timely manner.

Molecular genetic diagnosis by next-generation sequencing in a cohort of Mexican patients with haemophilia and report of novel variants.

Introduction: Molecular analysis in haemophilia is currently used in the diagnosis, treatment and prognosis of this disease. Hispanic populations in Latin America have been of interest to researchers due to the reportedly high prevalence of inhibitors in these patients.

Aim: To perform next-generation sequencing (NGS) in a cohort of Mexican patients with HA and HB and correlate with clinical phenotypes.

Genetic biomarkers related to hemarthrosis, inflammation, and cartilage structure in pediatric patients with hemophilic arthropathy.

Background: The pathophysiology of hemophilic arthropathy is complex and not completely understood. In this study, we aimed to identify biomarkers that can affect the hemophilic arthropathy severity.

Methods: Fifty patients were analyzed for biomarker frequencies; in 37 patients, articular symptoms were evaluated based on the physical joint examination score, and in 18, it was based on magnetic resonance imaging.

In silico analysis of missense mutations in exons 1-5 of the F9 gene that cause hemophilia B.

Background: Missense mutations in the first five exons of F9, which encodes factor FIX, represent 40% of all mutations that cause hemophilia B. To address the ongoing debate regarding in silico identification of disease-causing mutations at these exons, we analyzed 215 missense mutations from www.factorix.

F8 inversions of introns 22 and 1 confer a moderate risk of inhibitors in Mexican patients with severe hemophilia A. Concordance analysis and literature review.

Intron-22 (Inv22) and intron-1 (Inv1) inversions account for approximately one half of all severe cases of hemophilia A (SHA) worldwide. Inhibitor development against exogenous factor VIII (FVIII) represents a major complication in HA. The causative F8 mutation is considered the most decisive factor conditioning inhibitor development.

Molecular thrombophilic profile in Mexican patients with idiopathic recurrent pregnancy loss.

Idiopathic recurrent pregnancy loss (IRPL) is defined by three or more consecutive miscarriages occurring before the twentieth week of gestation as a result of unidentified etiological factors. The results of previous studies have indicated that prothrombotic factors play a pathogenic role in early and late pregnancy. This study aimed to identify inherited prothrombotic and hypofibrinolytic risk factors in Mexican-Mestizo patients with IRPL.

Two girls with a de novo Xq rearrangement of paternal origin: t(X;9)(q24;q12) or rea(X)dup q.

Objective: We report on two rare Xq rearrangements, namely a t(X;9)(q24;q12) found in a mildly-affected girl (Patient 1) and a rea(X)dup q concomitant with a rob(14;21)mat in a Down syndrome girl (Patient 2).

Case Report: Both rearrangements were characterized by banding techniques [Giemsa (G), constitutive heterochromatin (C), and bromodeoxyuridine (BrdU) pulse], fluorescence in situ hybridization (FISH) assays, human androgen receptor (HUMAR) assays, and microarray analyses. Patient 1 had a t(X;9)(q24;q12)dn.

Thrombin generation and international normalized ratio in inherited thrombophilia patients receiving thromboprophylactic therapy.

Background: Thrombin generation assay (TGA) is useful as a global functional test for assessing bleeding or thrombotic risk and its modification with therapy. We investigated TGA to assess anticoagulation status compared with the international normalized ratio (INR) system in patients with primary thrombophilia receiving and not undergoing thromboprophylaxis.

Materials And Methods: We studied 50 patients with at least one thrombotic event and a confirmed diagnosis of inherited thrombophilia.

[Diagnostic algorithm for von Willebrand Disease (vWD) in a Mexican population].

The diagnosis of von Willebrand disease (vWD) is complex and requires several screening and confirmation tests, such as the analysis of vWF multimers, which is considered the gold standard for vWD subtyping; however, it only discriminates 2A subtype while the 2B, 2M, and 2N subtypes require additional tests and even genetic testing for final confirmation. It is important to consider the patients’ hemotype for the vWD diagnosis, particularly in Mexico where hemotype “O” predominates and may entail a 20-25% decreased level of plasma vWF and increased bleeding tendency.

[The skin as a vehicle for gene therapy: hemophilia B, an application model].

Artificial skin offers important advantages in gene therapy tor its biosafety and simple monitoring. An easy access of keratinocytes through small biopsies and their in vitro expansion enriched with epithelial stem cells, make them an ideal target for long-term therapeutic transgene expression. Corrective cutaneous gene therapy has been recently applied in clinical trials on dermatological genetic diseases.

Thrombin generation as objective parameter of treatment response in patients with severe haemophilia A and high-titre inhibitors.

In Mexico, 15% of haemophilia A (HA) patients develop inhibitory alloantibodies in response to replacement therapy with factor VIII (FVIII), requiring bypass therapy such as activated prothrombin complex concentrate (APCC). Because bypass therapy has not been broadly available in Mexico even in recent years, this study aimed to evaluate the thrombin generation assay (TGA) in assessing the response to FVIII or APCC treatment in patients with severe HA positive to inhibitors. We studied 189 patients with severe HA.

Kinetics of factor VIII:C inhibitors and treatment response in severe hemophilia A patients.

Severe hemophilia A (HA) patients develop inhibitory alloantibodies to factor VIII:C and therefore require bypass agents that are scarce, expensive and may provoke secondary effects. Twenty-three severe HA patients who were high-responders to FVIII inhibitors were studied. FVIII:C activity in plasma was measured by one-stage activated partial thromboplastin time method, and the quantification of FVIII:C inhibitors was carried out by the Nijmegen-Bethesda method.

[Assessing the inactivation pattern in chromosome X among symptomatic carriers and women with haemophilia].

X chromosome inactivation is a stochastic event that occurs early in female embryo development to achieve dosage compensation with males. Certain genetic mechanisms affect the normal process causing a skewed X inactivation pattern which has clinical relevance in female carriers of X-linked recessive disorders, like haemophilia. The most commonly used assay to evaluate the X inactivation pattern is the PCR amplification of the human androgen receptor gene (HUMARA).

Molecular study of VWF gene from Mexican Mestizo patients with von Willebrand disease, and the finding of three new mutations.

To investigate the origin of von Willebrand disease in Mexican Mestizo population, we analyzed exons 18, 19, 20, 28, 45, and 52 of the VWF gene from 34 Mexican Mestizo index cases, 28 of them affected but not related, using DNA amplification by polymerase chain reaction and direct sequencing. We found three novel mutations: E1447Q in one patient with type 1; P2781S in one patient with type 2M; and P812L in another type 1/2N patient. These mutations were not found in 100 normal alleles.

Frequency of intron 1 and 22 inversions of Factor VIII gene in Mexican patients with severe hemophilia A.

Hemophilia A (HA) is one of the most common inherited bleeding disorders caused by FVIII gene mutations. Inversion of intron 22 (inv22) originates 50% of cases of severe HA and is a major risk factor for inhibitor development. Inversion of intron 1 (inv1) has been reported to occur in 2-3% of severe HA patients.

Thrombin generation and phenotypic correlation in haemophilia A.

The clinical phenotype of patients with haemophilia A (HA) often differs between individuals with the same factor VIII (FVIII) gene defect (e.g. within the same family) or the same coagulant activity of FVIII (FVIII:C).

High sensitivity of chemiluminescent methodology for detection of clonal CDR3 sequences in patients with acute lymphoblastic leukemia.

Detection of minimal residual disease (MRD) in patients with B-cell acute lymphoblastic leukemia (B-ALL) has been achieved using several radioactive labelling methodologies; however, limited information exists about the use of chemiluminescent labelling. Although many malignant disorders are related to cytogenetic alterations, there is not a consistent chromosomal translocation that could serve as a tumour marker for the monitoring of MRD. ALL are derived from B-lymphocytes in 80% of cases.

Detection and monitoring of clonality in peripheral blood and bone marrow of patients with B-cell lymphoproliferative disorders.

Bone marrow (BM) is accepted as the tissue of choice for the detection of monoclonal populations in leukemias and lymphomas; however, obtaining BM can be painful and traumatic for the patients. Although it is possible to detect clonality in peripheral blood (PB) samples, there are no reports comparing the results observed from BM with those from PB. Lymphoblastic leukemias and lymphomas are derived from B-lymphocytes in 80% of cases.