Hematology Commons^™

Randomized Phase Iii Bmt Ctn Trial Of Calcineurin Inhibitor-Free Chronic Graft-Versus-Host Disease Interventions In Myeloablative Hematopoietic Cell Transplantation For Hematologic Malignancies, Leo Luznik, Marcelo C Pasquini, Brent Logan, Robert J Soiffer, Juan Wu, Steven M Devine, Nancy Geller, Sergio Giralt, Helen E Heslop, Mary M Horowitz, Richard J Jones, Mark R Litzow, Adam Mendizabal, Lori Muffly, Eneida R Nemecek, Lynn O'Donnell, Richard J O'Reilly, Raquel Palencia, Johannes Schetelig, Leyla Shune, Scott R Solomon, Sumithira Vasu, Vincent T Ho, Miguel-Angel Perales

Faculty, Staff and Students Publications

PURPOSE: Calcineurin inhibitors (CNI) are standard components of graft-versus-host disease (GVHD) prophylaxis after hematopoietic cell transplantation (HCT). Prior data suggested that CNI-free approaches using donor T-cell depletion, either by ex vivo CD34 selection or in vivo post-transplant cyclophosphamide (PTCy) as a single agent, are associated with lower rates of chronic GVHD (cGVHD).

METHODS: This multicenter phase III trial randomly assigned patients with acute leukemia or myelodysplasia and an HLA-matched donor to receive CD34-selected peripheral blood stem cell, PTCy after a bone marrow (BM) graft, or tacrolimus and methotrexate after BM graft (control). The primary end point was cGVHD (moderate or …

Impact Of Frontline Treatment Approach On Outcomes In Patients With Secondary Aml With Prior Hypomethylating Agent Exposure, Nicholas J Short, Sangeetha Venugopal, Wei Qiao, Tapan M Kadia, Farhad Ravandi, Walid Macaron, Courtney D Dinardo, Naval Daver, Marina Konopleva, Gautam Borthakur, Elizabeth J Shpall, Uday Popat, Richard E Champlin, Rohtesh Mehta, Gheath Al-Atrash, Betul Oran, Elias Jabbour, Guillermo Garcia-Manero, Ghayas C Issa, Guillermo Montalban-Bravo, Musa Yilmaz, Abhishek Maiti, Hagop Kantarjian

Faculty, Staff and Student Publications

BACKGROUND: Treated secondary acute myeloid leukemia (ts-AML)-i.e., AML arising from a previously treated antecedent hematologic disorder-is associated with very poor outcomes. The optimal frontline treatment regimen for these patients is uncertain.

METHODS: We retrospectively analyzed 562 patients who developed AML from preceding myelodysplastic syndrome or chronic myelomonocytic leukemia for which they had received a hypomethylating agent (HMA). Patients with ts-AML were stratified by frontline AML treatment with intensive chemotherapy (IC, n = 271), low-intensity therapy (LIT) without venetoclax (n = 237), or HMA plus venetoclax (n = 54).

RESULTS: Compared with IC or LIT without venetoclax, HMA plus venetoclax resulted …

Prediction Of Early (4-Week) Mortality In Acute Myeloid Leukemia With Intensive Chemotherapy, Koji Sasaki, Tapan Kadia, Kebede Begna, Courtney D Dinardo, Gautam Borthakur, Nicholas J Short, Nitin Jain, Naval Daver, Elias Jabbour, Guillermo Garcia-Manero, Guillermo Montalban Bravo, Lucia Masarova, Sherry Pierce, Marina Konopleva, Farhad Ravandi, Ayalew Tefferi, Hagop Kantarjian

Faculty, Staff and Student Publications

The progress with intensive chemotherapy and supportive care measures has improved survival in patients with newly diagnosed acute myeloid leukemia (AML). Given the recent development of effective low intensity therapies, an optimal decision on the therapy intensity may improve survival through the avoidance of early mortality. We reviewed the outcome of 3728 patients with newly diagnosed AML who received intensive chemotherapy between August 1980 and May 2020. Intensive chemotherapy was defined as a cumulative cytarabine dose ≥ 700 mg/m2 during induction therapy. We divided the whole cohort into a training and validation group at a 3:1 ratio. The population was …

Impact Of Social Isolation In Hiv-Positive Individuals During A Pandemic, Corina Jane Bakoylis

Dissertations

Problem: The global pandemic of COVID-19 caused concern for immunocompromised individuals. The purpose of this quality improvement initiative was to assess the impact of social isolation on feelings of loneliness, depression, and social isolation experiences in HIV-positive individuals residing in a long-term care facility.

Methods: A mixed-method convergent design with a purposeful sample of HIV-positive adult residents residing in a long-term care facility was utilized. An evaluation of loneliness using the University of California Los Angeles (UCLA) Loneliness Scale (Version 3) and depression using the Patient Health Questionnaire-8 (PHQ-8) were completed. Personal experiences were also assessed with five predetermined open-ended …

Opioids Are Not A Major Cause Of Death Of Patients With Sickle Cell Disease., Samir K. Ballas

Cardeza Foundation for Hematologic Research

According to the Center of Disease Control and Prevention (CDC) database, the total number of deaths due to opioid overdose from 1999 through 2018 was 840,629. Given the alarming nature of these statistics, patients who requested prescription for opioids became targets of suspicion and possible accusation of maladaptive behavior. Patients with sickle cell disease (SCD) were often not exempt from such accusations and became guilty by association. In order to clarify the effect of opioids on the mortality of patients with SCD, the mortality rates for children and adults with SCD were investigated using the CDC Wide-ranging Online Data for …

Targeting Nsd2-Mediated Src-3 Liquid-Liquid Phase Separation Sensitizes Bortezomib Treatment In Multiple Myeloma, Jing Liu, Ying Xie, Jing Guo, Xin Li, Jingjing Wang, Hongmei Jiang, Ziyi Peng, Jingya Wang, Sheng Wang, Qian Li, Linquan Ye, Yuping Zhong, Qiguo Zhang, Xiaozhi Liu, David M Lonard, Jin Wang, Bert W O'Malley, Zhiqiang Liu

Faculty, Staff and Students Publications

Development of chemoresistance is the main reason for failure of clinical management of multiple myeloma (MM), but the genetic and epigenetic aberrations that interact to confer such chemoresistance remains unknown. In the present study, we find that high steroid receptor coactivator-3 (SRC-3) expression is correlated with relapse/refractory and poor outcomes in MM patients treated with bortezomib (BTZ)-based regimens. Furthermore, in immortalized cell lines, high SRC-3 enhances resistance to proteasome inhibitor (PI)-induced apoptosis. Overexpressed histone methyltransferase NSD2 in patients bearing a t(4;14) translocation or in BTZ-resistant MM cells coordinates elevated SRC-3 by enhancing its liquid-liquid phase separation to supranormally modify histone …

Bax 335 Hemophilia B Gene Therapy Clinical Trial Results: Potential Impact Of Cpg Sequences On Gene Expression, Barbara A Konkle, Christopher E Walsh, Miguel A Escobar, Neil C Josephson, Guy Young, Annette Von Drygalski, Scott W J Mcphee, R Jude Samulski, Ivan Bilic, Maurus De La Rosa, Birgit M Reipert, Hanspeter Rottensteiner, Friedrich Scheiflinger, John C Chapin, Bruce Ewenstein, Paul E Monahan

Faculty, Staff and Student Publications

Gene therapy has the potential to maintain therapeutic blood clotting factor IX (FIX) levels in patients with hemophilia B by delivering a functional human F9 gene into liver cells. This phase 1/2, open-label dose-escalation study investigated BAX 335 (AskBio009, AAV8.sc-TTR-FIXR338Lopt), an adeno-associated virus serotype 8 (AAV8)-based FIX Padua gene therapy, in patients with hemophilia B. This report focuses on 12-month interim analyses of safety, pharmacokinetic variables, effects on FIX activity, and immune responses for dosed participants. Eight adult male participants (aged 20-69 years; range FIX activity, 0.5% to 2.0%) received 1 of 3 BAX 335 IV doses: 2.0 × 1011; …

Reduced Intensity Conditioning For Acute Myeloid Leukemia Using Melphalan- Vs Busulfan-Based Regimens: A Cibmtr Report, Zheng Zhou, Rajneesh Nath, Jan Cerny, Hai-Lin Wang, Mei-Jie Zhang, Hisham Abdel-Azim, Vaibhav Agrawal, Gulrayz Ahmed, A Samer Al-Homsi, Mahmoud Aljurf, Hassan B Alkhateeb, Amer Assal, Ulrike Bacher, Ashish Bajel, Qaiser Bashir, Minocher Battiwalla, Vijaya Raj Bhatt, Michael Byrne, Jean-Yves Cahn, Mitchell Cairo, Hannah Choe, Edward Copelan, Corey Cutler, Moussab B Damlaj, Zachariah Defilipp, Marcos De Lima, Miguel Angel Diaz, Nosha Farhadfar, James Foran, César O Freytes, Aaron T Gerds, Usama Gergis, Michael R Grunwald, Zartash Gul, Mehdi Hamadani, Shahrukh Hashmi, Mark Hertzberg, Gerhard C Hildebrandt, Nasheed Hossain, Yoshihiro Inamoto, Luis Isola, Tania Jain, Rammurti T Kamble, Muhammad Waqas Khan, Mohamed A Kharfan-Dabaja, Partow Kebriaei, Natasha Kekre, Nandita Khera, Hillard M Lazarus, Jane L Liesveld, Mark Litzow, Hongtao Liu, David I Marks, Rodrigo Martino, Vikram Mathews, Asmita Mishra, Hemant S Murthy, Arnon Nagler, Ryotaro Nakamura, Sunita Nathan, Taiga Nishihori, Rebecca Olin, Richard F Olsson, Neil Palmisiano, Sagar S Patel, Mrinal M Patnaik, Attaphol Pawarode, Miguel-Angel Perales, Ioannis Politikos, Uday Popat, David Rizzieri, Brenda M Sandmaier, Bipin N Savani, Sachiko Seo, Nirav N Shah, Geoffrey L Uy, David Valcárcel, Leo F Verdonck, Edmund K Waller, Youjin Wang, Daniel Weisdorf, Baldeep Wirk, Eric Wong, Jean A Yared, Wael Saber

Faculty, Staff and Students Publications

There is a lack of large comparative study on the outcomes of reduced intensity conditioning (RIC) in acute myeloid leukemia (AML) transplantation using fludarabine/busulfan (FB) and fludarabine/melphalan (FM) regimens. Adult AML patients from Center for International Blood and Marrow Transplant Research who received first RIC allo-transplant between 2001 and 2015 were studied. Patients were excluded if they received cord blood or identical twin transplant, total body irradiation in conditioning, or graft-versus-host disease (GVHD) prophylaxis with in vitro T-cell depletion. Primary outcome was overall survival (OS), secondary end points were leukemia-free survival (LFS), nonrelapse mortality (NRM), relapse, and GVHD. Multivariate survival …

The Concentration Of Total Nucleated Cells In Harvested Bone Marrow For Transplantation Has Decreased Over Time., Nicole L. Prokopishyn, Brent R. Logan, Deidre M. Kiefer, Jennifer A. Sees, Pintip Chitphakdithai, Ibrahim A. Ahmed, Paolo N. Anderlini, Amer M. Beitinjaneh, Christopher Bredeson, Jan Cerny, Saurabh Chhabra, Andrew Daly, Miguel Angel Diaz, Nosha Farhadfar, Haydar A. Frangoul, Siddhartha Ganguly, Dennis A. Gastineau, Usama Gergis, Gregory A. Hale, Peiman Hematti, Rammurti T. Kamble, Kimberly A. Kasow, Hillard M. Lazarus, Jane L. Liesveld, Hemant S. Murthy, Maxim Norkin, Richard F. Olsson, Mona Papari, Bipin N. Savani, Jeffrey Szer, Edmund K. Waller, Baldeep Wirk, Jean A. Yared, Michael A. Pulsipher, Nirali N. Shah, Galen E. Switzer, Paul V. O'Donnell, Dennis L. Confer, Bronwen E. Shaw

Manuscripts, Articles, Book Chapters and Other Papers

Bone marrow (BM) is an essential source of hematopoietic stem cell grafts for many allogeneic hematopoietic cell transplant (HCT) recipients, including adult patients (for specific diseases and transplantation strategies) and the majority of pediatric recipient. However, since the advent of granulocyte colony-stimulating factor-mobilized peripheral blood stem cell (PBSC) grafts, there has been a significant decrease in the use of BM in HCT, thought to be due mainly to the increased logistical challenges in harvesting BM compared with PBSCs, as well as generally no significant survival advantage of BM over PBSCs. The decreased frequency of collection has the potential to impact …

Effect Of Conditioning Regimen Dose Reduction In Obese Patients Undergoing Autologous Hematopoietic Cell Transplantation., Claudio G. Brunstein, Marcelo C. Pasquini, Soyoung Kim, Mingwei Fei, Kehinde Adekola, Ibrahim A. Ahmed, Mahmoud Aljurf, Vaibhav Agrawal, Jeffrey J. Auletta, Minoo Battiwalla, Nelli Bejanyan, Joseph Bubalo, Jan Cerny, Lynette Chee, Stefan O. Ciurea, Cesar Freytes, Shahinaz M. Gadalla, Robert Peter Gale, Siddhartha Ganguly, Shahrukh K. Hashmi, Peiman Hematti, Gerhard Hildebrandt, Leona A. Holmberg, Oscar B. Lahoud, Heather Landau, Hillard M. Lazarus, Marcos De Lima, Vikram Mathews, Richard Maziarz, Taiga Nishihori, Maxim Norkin, Richard Olsson, Ran Reshef, Seth Rotz, Bipin Savani, Harry C. Schouten, Sachiko Seo, Baldeep M. Wirk, Jean Yared, Shin Mineishi, John Rogosheske, Miguel-Angel Perales

Manuscripts, Articles, Book Chapters and Other Papers

Data are limited on whether to adjust high-dose chemotherapy before autologous hematopoietic cell transplant (autoHCT) in obese patients. This study explores the effects of dose adjustment on the outcomes of obese patients, defined as body mass index (BMI) ≥ 30 kg/m2. Dose adjustment was defined as a reduction in standard dosing ≥20%, based on ideal, reported dosing and actual weights. We included 2 groups of US patients who had received autoHCT between 2008 and 2014. Specifically, we included patients with multiple myeloma (MM, n = 1696) treated with high-dose melphalan and patients with Hodgkin or non-Hodgkin lymphomas (n = 781) …

Clinical Pharmacology Of Tisagenlecleucel In B-Cell Acute Lymphoblastic Leukemia., Karen Thudium Mueller, Edward Waldron, Stephan A. Grupp, John E. Levine, Theodore W. Laetsch, Michael A. Pulsipher, Michael W. Boyer, Keith August, Jason Hamilton, Rakesh Awasthi, Andrew M. Stein, Denise Sickert, Abhijit Chakraborty, Bruce L. Levine, Carl H. June, Lori Tomassian, Sweta S. Shah, Mimi Leung, Tetiana Taran, Patricia A. Wood, Shannon L. Maude

Manuscripts, Articles, Book Chapters and Other Papers

PURPOSE: Tisagenlecleucel is an anti-CD19 chimeric antigen receptor (CAR19) T-cell therapy approved for the treatment of children and young adults with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (B-ALL).

PATIENTS AND METHODS: We evaluated the cellular kinetics of tisagenlecleucel, the effect of patient factors, humoral immunogenicity, and manufacturing attributes on its kinetics, and exposure-response analysis for efficacy, safety and pharmacodynamic endpoints in 79 patients across two studies in pediatric B-ALL (ELIANA and ENSIGN).

RESULTS: Using quantitative polymerase chain reaction to quantify levels of tisagenlecleucel transgene, responders (N = 62) had ≈2-fold higher tisagenlecleucel expansion in peripheral blood than nonresponders ( …

Distribution Of Chromosomal Abnormalities Commonly Observed In Adult Acute Myeloid Leukemia In Pakistan As Predictors Of Prognosis, Muhammad Shariq Shaikh, Zeeshan Ansar Ahmed, Mohammad Usman Shaikh, Salman Naseem Adil, Mohammad Khurshid, Tariq Moatter, Anila Rashid, Farheen Karim, Ahmed Raheem, Natasha Ali

Department of Pathology and Laboratory Medicine

Objectives: The heterogenous response to treatment in acute myeloid leukemia (AML) can be attributed largely to the difference in cytogenetic features identified in between cases. Cytogenetic analysis in acute leukemia is now routinely used to assist patient management, particularly in terms of diagnosis, disease monitoring, prognosis and risk stratification. Knowing about cytogenetic profile at the time of diagnosis is important in order to take critical decisions in management of these patients. The study was conducted to determine the distribution of cytogenetic abnormalities in Pakistani adult patients with AML in order to have insights regarding behavior of the disease.
Methods: A …

Age Adjusted Hematopoietic Stem Cell Transplant Comorbidity Index Predicts Survival In A T-Cell Depleted Cohort, Hayder Saeed, Swati Yalamanchi, Meng Liu, Emily Van Meter, Zartash Gul, Gregory Monohan, Dianna Howard, Gerhard C. Hildebrandt, Roger Herzig

Markey Cancer Center Faculty Publications

Objectives: Allogeneic hematopoietic stem cell transplant (HCT) continues to evolve with the treatment in higher risk patient population. This practice mandates stringent update and validation of risk stratification prior to undergoing such a complex and potentially fatal procedure. We examined the adoption of the new comorbidity index (HCT-CI/Age) proposed by the Seattle group after the addition of age variable and compared it to the pre-transplant assessment of mortality (PAM) that already incorporates age as part of its evaluation criteria.

Methods: A retrospective analysis of adult patients who underwent HCT at our institution from January 2010 through August 2014 was …

Iron Isomaltoside Is Superior To Iron Sucrose In Increasing Hemoglobin In Gynecological Patients With Iron Deficiency Anemia., Richard Derman, Eloy Roman, Gioi N. Smith-Nguyen, Maureen M. Achebe, Lars L. Thomsen, Michael Auerbach

Global Health Articles

No abstract provided.

Sickle Cell Disease: Classification Of Clinical Complications And Approaches To Preventive And Therapeutic Management., Samir K. Ballas

Department of Medicine Faculty Papers

Sickle cell disease (SCD) is an inherited disorder of hemoglobin structure that has no established cure in adult patients. Cure has been achieved in selected children with sickle cell anemia (SCA) using allogeneic bone marrow transplantation or cord blood transplantation. SCD is essentially a triumvirate of (1) pain syndromes, (2) anemia and its sequelae and (3) organ failure, including infection. Pain, however, is the hallmark of SCD and dominates its clinical picture throughout the life of the patients. The prevalence of these complications varies with age from infancy through adult life. However, pain, infections and anemia requiring blood transfusion occur …

Multimodality Therapy Improves Survival In Intramedullary Spinal Cord Metastasis Of Lung Primary, Hayder Saeed, Reema Patel, Jigisha Thakkar, Lames Hamoodi, Li Chen, John L. Villano

Internal Medicine Faculty Publications

Background: Most metastatic spinal cord lesions are located either in the intradural, extramedullary, or in the epidural compartments. Intramedullary spinal cord metastasis (ISCM) is a rare central nervous system spread of cancer. The aim of this report was to evaluate ISCM in the published literature.

Methods: A literature review of PubMed from 1960 to 2016 was undertaken for the publications having demographic, clinical, histological, and outcome data.

Results: A total of 59 relevant papers were identified, showing 128 cases of intramedullary metastasis from lung cancer. The incidence of lung cancer as the primary malignancy with intramedullary metastasis was 56%. The …

Strategies To Improve Control Of Blood A1c In Diabetics, Jennifer Aronson, Leanne Bellino, Elizabeth Eisenhardt, Diane Bryant, Haley Pelletier, Internal Medicine Team, Adult Outpatient Clinic

MaineHealth Maine Medical Center

A1c monitoring is an important aspect of controlling the health of a diabetic patient. An adult internal medicine clinic noted that the percentage of their diabetic patients who had an A1c higher than 9 or no reading within the past year exceeded the national average. As a result, operational excellence methods were implemented with the overall goal to reduce their percentage to 18% or less.

A root cause analysis identified several deficiencies to includelack of essential equipment, variations in

staff education and the absence of daily reminders.

Post KPI implementations, an overall decrease in the percentage of patients with poorly …

Novel Hla-Dp Region Susceptibility Loci Associated With Severe Acute Gvhd., Rakesh K. Goyal, S J. Lee, T Wang, M Trucco, M Haagenson, S R. Spellman, M Verneris, R E. Ferrell

Manuscripts, Articles, Book Chapters and Other Papers

Despite HLA allele matching, significant acute GvHD remains a major barrier to successful unrelated donor BMT. We conducted a genome-wide association study (GWAS) to identify recipient and donor genes associated with the risk of acute GvHD. A case-control design (grade III-IV versus no acute GvHD) and pooled GWA approach was used to study European-American recipients with hematological malignancies who received myeloablative conditioning non-T-cell-depleted first transplantation from HLA-A, -B, -C, -DRB1, -DQB1 allele level (10/10) matched unrelated donors. DNA samples were divided into three pools and tested in triplicate using the Affymetrix Genome-wide SNP Array 6.0. We identified three novel susceptibility …

Targeted Mutational Profiling Of Peripheral T-Cell Lymphoma Not Otherwise Specified Highlights New Mechanisms In A Heterogeneous Pathogenesis., J. H. Schatz, S. M. Horwitz, J. Teruya-Feldstein, Matthew A. Lunning, A. Viale, K. Huberman, N. D. Socci, N. Lailler, A. Heguy, I. Dolgalev, J. C. Migliacci, M. Pirun, M. L. Palomba, D. M. Weinstock, H-G Wendel

Journal Articles: Oncology and Hematology

No abstract provided.

Calcium Supplementation Increases Blood Creatinine Concentration In A Randomized Controlled Trial, Elizabeth L. L. Barry, Leila A. A. Mott, Michal L. L. Melamed, Judith R. Rees, Anastasia Ivanova, Robert S. Sandler, Dennis J. Ahnen, Robert S. Bresalier, Robert W. Summers, Roberd M. Bostick, John A. Baron

Dartmouth Scholarship

Background: Calcium supplements are widely used among older adults for osteoporosis prevention and treatment. However, their effect on creatinine levels and kidney function has not been well studied.

Methods: We investigated the effect of calcium supplementation on blood creatinine concentration in a randomized controlled trial of colorectal adenoma chemoprevention conducted between 2004–2013 at 11 clinical centers in the United States. Healthy participants (N=1,675) aged 45–75 with a history of colorectal adenoma were assigned to daily supplementation with calcium (1200 mg, as carbonate), vitamin D3 (1000 IU), both, or placebo for three or five years. Changes in blood creatinine and total …

Cdx4 Dysregulates Hox Gene Expression And Generates Acute Myeloid Leukemia Alone And In Cooperation With Meis1a In A Murine Model, Dimple Bansal, Claudia Scholl, Stefan Frohling, Elizabeth Mcdowell, Benjamin H. Lee, Konstanze Döhner, Patricia Ernst

Dartmouth Scholarship

HOX genes have emerged as critical effectors of leukemogenesis, but the mechanisms that regulate their expression in leukemia are not well understood. Recent data suggest that the caudal homeobox transcription factors CDX1, CDX2, and CDX4, developmental regulators of HOX gene expression, may contribute to HOX gene dysregulation in leukemia. We report here that CDX4 is expressed normally in early hematopoietic progenitors and is expressed aberrantly in approximately 25% of acute myeloid leukemia (AML) patient samples. Cdx4 regulates Hox gene expression in the adult murine hematopoietic system and dysregulates Hox genes that are implicated in leukemogenesis. Furthermore, bone marrow progenitors that …

Spectrum Of Hodgkin's Disease In Children And Adults: Impact Of Combined Morphologic And Phenotypic Approach For Exclusion Of Look-Alikes, Tanya Siddiqui, Shahid Pervez

Department of Pathology and Laboratory Medicine

Objective:

To determine the prevalence of Hodgkin’s disease (HD) and its various subtypes in children and adults and assess the use of immunohistochemical (IHC) studies in confirming HD cases and excluding its close mimicries/look-alikes.

Material and Methods:

All 265 Hodgkin’s disease cases diagnosed at The Aga Khan University Hospital, Karachi over the last 6 years (July 1991 - July 1997) were included. Of these 219 were diagnosed on routine H&E examination while in the remaining 46 cases, diagnosis was made after a thorough IHC workup. (This group initially included 161 cases labelled as lymphoproliferative disorder with HD as one of …

Glanzmann Thrombasthenia. Cooperation Between Sequence Variants In Cis During Splice Site Selection., Ying Jin, Harry C. Dietz, Robert A. Montgomery, William R. Bell, Iain Mcintosh, Barry Coller, Paul F. Bray

Cardeza Foundation for Hematologic Research

Glanzmann thrombasthenia (GT), an autosomal recessive bleeding disorder, results from abnormalities in the platelet fibrinogen receptor, GP(IIb)-IIIa (integrin alpha(IIb)beta3). A patient with GT was identified as homozygous for a G-->A mutation 6 bp upstream of the GP(IIIa) exon 9 splice donor site. Patient platelet GP(IIIa) transcripts lacked exon 9 despite normal DNA sequence in all of the cis-acting sequences known to regulate splice site selection. In vitro analysis of transcripts generated from mini-gene constructs demonstrated that exon skipping occurred only when the G-->A mutation was cis to a polymorphism 116 bp upstream, providing precedence that two sequence variations …