Complete Genotype and Clinical Phenotype of Hemophilia B: A Study on Iranian Patients

Background: Hemophilia B which refers to the deficiency or functional defect of factor IX (FIX) is typically an X-linked bleeding condition that arises from heterogeneous mutations of the FIX gene (F9). The number of hemophilia cases in Iran is considerable and currently, about 1118 Iranian patients are suffering from hemophilia B, although a small number of them underwent genetic investigations. Here we assessed molecular defects and also laboratory and clinical findings of 10 Iranian cases with hemophilia B. Materials and Methods: A total of 10 cases with hemophilia B were enrolled in the study. Patients were clinically examined by a hematologist and their previous medical documents were surveyed carefully. Routine coagulation tests and FIX activity and antigen assays were performed for the studied patients. Genotyping of F9 for identifying genetic mutations was conducted by the Sanger sequencing method following PCR amplification of the promoter region and all the eight exons of the F9 gene. Results: The mean age of patients was 4 years (9 months to 16 years) and consanguinity was reported in 80% of cases. Patients were commonly manifested by hematoma (90%), epistaxis (80%), and hemarthrosis (70%) and the severity of the disorder was severe (70%) or moderate (30%). In nine out of 10 patients a genetic defect in F9 gene we detected including three missense (c.304T>C, c.1007T>A, c.191G>A) and three nonsense mutations (c.892C>T, c.880C>T, c.1113C>A). Based on the FIX variant database (http://www.factorix.org), five mutations have been reported previously, but mutation c.1007T>A (p.Ile336Asn) seems to be a novel mutation. Conclusion: Our results indicated the heterogeneous molecular defects of hemophilia B in Iran, as recorded in the FIX mutation database. Moreover, no specific genotype-phenotype association was observed in studied subjects

Compositions and methods for lipid production

Described herein, inter alia, are compositions, oleagnious organisms, and methods useful for producing lipids, lipid precursors, and/or oleochemicals.Board of Regents, University of Texas Syste

Molecular genetic study of hemophilia B in an Algerian population

Hemophilia B is inherited as x-linked recessive disorder, carried by females, where males are affected.Rare cases of females affected with hemophilia B are known. This is also known as factor IX (FIX)deficiency, or "Christmas disease", originally named after Stephen Christmas; the first patient wasdescribed with this disease in 1952. It is characterized by spontaneous or prolonged hemorrages due tofactor IX deficiency. Factor IX mutations have not been previously reported in Algerian patients. Tounderstand the molecular basis of hemophilia B in Algeria, polymerase chain reaction (PCR) and directsequencing have been applied to be the important regions of the factor IX gene from 11 patients; weidentified 2 point mutations. Mutations identified in our patients was linked with disease severity.Complications are problems that develop during treatment of the disease. Inhibitor (alloantibodies toexogenous factor XI) development is currently the most significant treatment complication. In thisstudy, we evaluated the relationship between inhibitor development and FIX gene mutation types. Insummary, our preliminary results will be used to build an Algerian mutation database which wouldfacilitate genetic counseling.Key words: Hemophilia B, factor IX gene, mutation, inhibitors

Prognostic and therapeutic value of somatic mutations in diffuse large B-cell lymphoma: A systematic review

Diffuse large B-cell lymphoma (DLBCL), the most common type of Non-Hodgkin lymphoma (NHL), is a highly heterogeneous and aggressive disease. Regardless of this heterogeneity, all patients receive the same first-line therapy, which fails in 30-40 % of patients, who are either refractory or relapse after remission. With the aim of stratifying patients to improve treatment outcome, different clinical and genetic biomarkers have been studied. The present systematic review aimed to identify somatic mutations that could serve as prognosis biomarkers or as therapeutic target mutations in DLBCL. Regarding their role as prognostic markers, mutations in CD58 and TP53 seem the most promising predictors of poor outcome although the combination of different alterations and other prognostic factors could be a more powerful strategy. On the other hand, different approaches regarding targeted therapy have been proposed. Therefore, mutational analysis could help guide treatment choice in DLBCL yet further studies and clinical trials are needed.This study was funded by the Basque Government (IT989-16) and EiTB maratoia/Bioef (BIO15/CA/022/BC) . AGC was supported by a post-doctoral grant from the Basque Government

Analysis of CLDN14 gene in deaf Moroccan patients with non-syndromic hearing loss

Mutations in the CLDN14 gene, encoding the tight junction claudin 14 protein has been reported to date in an autosomal recessive form of isolated hearing loss DFNB29. In order to identify the contribution of CLDN14 to inherited deafness in Moroccan population, we performed a genetic analysis of this gene in 80 Moroccan familial cases. Our results show the presence of 7 mutations: 6 being conservative and one leading to a missense mutation (C11T) which was found at heterozygous and homozygous states, with a general frequency of 6.87%. The pathogenicity of the resulting T4M substitution is under discussion. Finally, our study suggests that CLDN14 gene can be implicated in the development of hearing loss in the Moroccan population

A Recessive Mutation Resulting in a Disabling Amino Acid Substitution (T194R) in the LHX3 Homeodomain Causes Combined Pituitary Hormone Deficiency

Background/Aims: Recessive mutations in the LHX3 homeodomain transcription factor gene are associated with developmental disorders affecting the pituitary and nervous system. We describe pediatric patients with combined pituitary hormone deficiency (CPHD) who harbor a novel mutation in LHX3. Methods: Two female siblings from related parents were examined. Both patients had neonatal complications. The index patient had CPHD featuring deficiencies of GH, LH, FSH, PRL, and TSH, with later onset of ACTH deficiency. She also had a hypoplastic anterior pituitary, respiratory distress, hearing impairment, and limited neck rotation. The LHX3 gene was sequenced and the biochemical properties of the predicted altered proteins were characterized. Results: A novel homozygous mutation predicted to change amino acid 194 from threonine to arginine (T194R) was detected in both patients. This amino acid is conserved in the DNA-binding homeodomain. Computer modeling predicted that the T194R change would alter the homeodomain structure. The T194R protein did not bind tested LHX3 DNA recognition sites and did not activate the a-glycoprotein and PRL target genes. Conclusion: The T194R mutation affects a critical residue in the LHX3 protein. This study extends our understanding of the phenotypic features, molecular mechanism, and developmental course associated with mutations in the LHX3 gene. copyright (C) 2012 S. Karger AG, Base

Consequences of the pathogenic T9176C mutation of human mitochondrial DNA on yeast mitochondrial ATP synthase

Several human neurological disorders have been associated with various mutations affecting mitochondrial enzymes involved in cellular ATP production. One of these mutations, T9176C in the mitochondrial DNA (mtDNA), changes a highly conserved leucine residue into proline at position 217 of the mitochondrially encoded Atp6p (or a) subunit of the F1FO-ATP synthase. The consequences of this mutation on the mitochondrial ATP synthase are still poorly defined. To gain insight into the primary pathogenic mechanisms induced by T9176C, we have investigated the consequences of this mutation on the ATP synthase of yeast where Atp6p is also encoded by the mtDNA. In vitro, yeast atp6-T9176C mitochondria showed a 30% decrease in the rate of ATP synthesis. When forcing the F1FO complex to work in the reverse mode, i.e. F1-catalyzed hydrolysis of ATP coupled to proton transport out of the mitochondrial matrix, the mutant showed a normal proton-pumping activity and this activity was fully sensitive to oligomycin, an inhibitor of the ATP synthase proton channel. However, under conditions of maximal ATP hydrolytic activity, using non-osmotically protected mitochondria, the mutant ATPase activity was less efficiently inhibited by oligomycin (60% inhibition versus 85% for the wild type control). Blue Native Polyacrylamide Gel Electrophoresis analyses revealed that atp6-T9176C yeast accumulated rather good levels of fully assembled ATP synthase complexes. However, a number of sub-complexes (F1, Atp9p-ring, unassembled alpha-F1 subunits) could be detected as well, presumably because of a decreased stability of Atp6p within the ATP synthase. Although the oxidative phosphorylation capacity was reduced in atp6-T9176C yeast, the number of ATP molecules synthesized per electron transferred to oxygen was similar compared with wild type yeast. It can therefore be inferred that the coupling efficiency within the ATP synthase was mostly unaffected and that the T9176C mutation did not increase the proton permeability of the mitochondrial inner membrane

The Role of PTEN in Tumor Angiogenesis

During the past 20 years, the phosphatase and tensin homolog PTEN has been shown to be involved in major physiological processes, and its mutation or loss is often associated with tumor formation. In addition PTEN regulates angiogenesis not only through its antagonizing effect on the PI3 kinase pathway mainly, but also through some phosphatase-independent functions. In this paper we delineate the role of this powerful tumor suppressor in tumor angiogenesis and dissect the underlying molecular mechanisms. Furthermore, it appears that, in a number of cancers, the PTEN status determines the response to chemotherapy, highlighting the need to monitor PTEN expression and to develop PTEN-targeted therapies

Mutations in TUBG1, DYNC1H1, KIF5C and KIF2A cause malformations of cortical development and microcephaly

The genetic causes of malformations of cortical development (MCD) remain largely unknown. Here we report the discovery of multiple pathogenic missense mutations in TUBG1, DYNC1H1 and KIF2A, as well as a single germline mosaic mutation in KIF5C, in subjects with MCD. We found a frequent recurrence of mutations in DYNC1H1, implying that this gene is a major locus for unexplained MCD. We further show that the mutations in KIF5C, KIF2A and DYNC1H1 affect ATP hydrolysis, productive protein folding and microtubule binding, respectively. In addition, we show that suppression of mouse Tubg1 expression in vivo interferes with proper neuronal migration, whereas expression of altered gamma-tubulin proteins in Saccharomyces cerevisiae disrupts normal microtubule behavior. Our data reinforce the importance of centrosomal and microtubule-related proteins in cortical development and strongly suggest that microtubule-dependent mitotic and postmitotic processes are major contributors to the pathogenesis of MCD

Detection of Del Phenotype in RH negative blood by using chloroform elution technique and specific sequence Primer-Polymerase Chain Reaction (SSP-PCR) / Nor Arina Che Mohd Noor

DEL phenotype is known as the weakest D antigen in the Rh blood group system. Serologically, DEL phenotype commonly mistyped as true Rh negative. An anti-D immunization may occurred in Rh negative recipient who received blood from the DEL phenotype donor. The goals of the present study were to detect DEL phenotype in Rh negative blood by using chloroform elution technique and specific sequence primer-polymerase chain reaction (SSP-PCR). A total of 43 Rh negative blood donor's samples from National Blood Centre were examined for the Rh phenotyping and the presence of DEL phenotype by using chloroform elution technique and SSPPCR. The Rh negative phenotypes consisted of 79.07% dce, 13.95% dCce, 4.65% dcEe and 2.33% dCe. Chloroform elution technique failed to detect DEL phenotype, but only 2.33% (1/43) Rh negative blood donor's sample was being detected as DEL phenotype by using SSP-PCR. In conclusion, based on these findings, chloroform elution technique might not be an effective method in detection of DEL phenotype. Sensitivity and specificity of molecular typing method can overcome the limitation of serological method in the clinical laboratory. Hence, it is highly recommended to use SSP-PCR in detection of DEL phenotype in Rh negative blood, thus preventing the anti-D immunization