CRISPR, ZFNS, and TALENS for Hemoglobinopathies an Analysis

2021 ◽  
Vol 9 (11) ◽  
pp. 1238-1242
Author(s):  
Venya Khare
Keyword(s):  
Sickle Cell Disease ◽  
Genome Editing ◽  
Sickle Cell ◽  
Single Gene ◽  
The United States ◽  
Annual Number ◽  
Beta Thalassemia ◽  
Target Genome ◽  
Cell Disease ◽  
Transcription Activator

Abstract: Sickle Cell Disease is one of the most common genetic disorders in the United States and is incredibly prevalent throughout Africa and the Middle East. By 2050, the annual number of newborns with Sickle Cell Disease is projected to increase by 33%. A similar story can be told about Beta-Thalassemia: another hemoglobinopathy that has no standard treatment. The future of treating hemoglobinopathies looks bleak and more research must be done to prevent fatalities and the lifelong problems associated with it now. Sickle Cell Disease and Beta Thalassemia have one defining similarity: they are both monogenic disorders. This unique characteristic of having a single gene variation allows them to be the ideal candidate for one of the newest breakthroughs in biotechnology: target genome editing. As of now, there are three major competitors in the field, Zinc Finger Nuclease (ZFN), Transcription Activator-like Effector Nucleases (TALENs), and Clustered Regularly Interspaced Short Palindromic Repeat (CRISPR) target genome editing. Here I summarize the possibilities target genome editing provides in terms of research and a potential treatment for both Sickle Cell disease and Beta Thalassemia with a focus on comparing the three target genome editing technologies.

scholarly journals Clinical events in the first decade in a cohort of infants with sickle cell disease. Cooperative Study of Sickle Cell Disease [see comments]

Blood ◽  
1995 ◽  
Vol 86 (2) ◽  
pp. 776-783 ◽  
Author(s):  
FM Gill ◽  
LA Sleeper ◽  
SJ Weiner ◽  
AK Brown ◽  
R Bellevue ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Clinical Course ◽  
The United States ◽  
Beta Thalassemia ◽  
Acute Chest Syndrome ◽  
Cooperative Study ◽  
Cell Disease ◽  
Splenic Sequestration ◽  
Clinical Events

Within the Cooperative Study of Sickle Cell Disease, 694 infants with confirmed sickle cell disease were enrolled at less than 6 months of age. Information about the nature and frequency of complications was collected prospectively over a 10-year period. Painful crises and acute chest syndrome were the most common sickle cell-related events in homozygous sickle cell anemia (SS), hemoglobin SC disease (SC), and S beta thalassemia patients (overall incidence in SS patients of 32.4 and 24.5 cases per 100 person-years, respectively). Bacteremia occurred most frequently in SS children under 4 years of age and in SC patients less than 2 years of age. The mortality rate was low in this cohort compared with that found in previous reports. Twenty children, all with Hb SS, died (1.1 deaths per 100 person-years among SS patients). Infection, most commonly with Streptococcus pneumoniae and Hemophilus influenzae, caused 11 deaths. Two children died of splenic sequestration, 1 of cerebrovascular accident, and 6 of unclear causes. Two patients underwent cholecystectomies, and 17 underwent splenectomies after one or more splenic sequestration crises. The experience of this cohort should reflect closely the true clinical course of those children with Hb SS and Hb SC disease who are observed in sickle cell centers in the United States.

scholarly journals Clinical validity of single-gene non-invasive prenatal testing for sickle cell disease and beta thalassemia

2021 ◽  
Author(s):  
Erik R. Westin ◽  
David S. Tsao ◽  
Oguzhan Atay ◽  
Brian P. Landry ◽  
Patrick P. Ye ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Newborn Screening ◽  
Cord Blood ◽  
Sickle Cell ◽  
Single Gene ◽  
Beta Thalassemia ◽  
Carrier Status ◽  
Cell Disease ◽  
Non Invasive ◽  
Prenatal Detection

AbstractBackgroundSickle cell disease (SCD) and beta thalassemia (β-thalassemia) are among the most common and severe genetically inherited disorders in the world. Although the maternal carrier status of these beta hemoglobinopathies is screened as a part of routine prenatal care in the US, the paternal carrier status is usually unavailable. Under this current screening paradigm, identification of the majority of SCD and beta thalassemia cases could therefore be delayed until newborn screening results are available. An effective reflex, non-invasive prenatal test (NIPT) that uses only maternal blood would permit prenatal detection of sickle cell disease and beta thalassemia by screening for these disorders without the need for paternal DNA. This screening would enable patients and healthcare providers to make informed decisions about diagnostic testing, and it could expand gene therapy treatment options by requesting cord blood banking at delivery. We have previously developed a single-gene NIPT platform (UNITY™) for SCD and beta thalassemia with extensive analytic validation and initial clinical validation in our prior studies.ObjectivesThe objective of this study is to further assess the clinical validity of single-gene NIPT for SCD and beta thalassemia in a larger pregnancy population.Study DesignPregnant women who screened positive for at least one allele of a beta hemoglobinopathy were enrolled at two academic medical centers for this retrospective cohort study. Single-gene NIPT for SCD and beta thalassemia was performed in blinded fashion on maternal blood samples to determine the fetal genotype and disease status. Single-gene NIPT findings were compared with either newborn screen results or genotyping of umbilical cord blood.ResultsSingle-gene NIPT detection of fetuses that are affected versus unaffected with SCD and beta thalassemia was 100% concordant with newborn screening follow-up data, even in challenging samples that contained a low fetal fraction (<5%) or at earlier gestational ages. Additionally, we obtained 98.5% concordance with newborn genotypes, including differentiating healthy fetal sickle cell carriers from homozygous healthy fetuses. The sensitivity of detecting fetal carrier status of beta hemoglobinopathies was 100% (90.8% to 100% CI), and the specificity was 96.4% (81.7% to 99.9 % CI).ConclusionsSingle-gene NIPT is a highly accurate screen for prenatal detection of SCD and beta thalassemia. The results further suggest that the maternal carrier screen with reflex single-gene NIPT workflow can significantly improve the detection rates of at-risk pregnancies from <50% to >98%.AJOG at a GlanceA.Why was this study conducted?Effective non-invasive prenatal testing (NIPT) is needed to permit safe in utero diagnosis of sickle cell disease (SCD) and beta thalassemia (β-thalassemia), and permit collection and banking of cord blood for future cell therapy. We have previously developed a single-gene NIPT method for SCD and β-thalassemia, with extensive analytic validation and initial clinical validation in our prior studies.B.What are the key findings?Our single-gene NIPT detection of SCD and β-thalassemia disease was 100% concordant with newborn screening follow-up data in 79 pregnancies at risk for beta hemoglobinopathies. Furthermore, a more stringent requirement, the detection of exact fetal genotype, was concordant in 67 out of 68 (98.5%) of pregnancies.C.What does this study add to what is already known?Our results validated that single-gene NIPT is an accurate and significantly improved screen for prenatal detection of SCD and β-thalassemia compared to current carrier screen workflow.

Red cell storage age policy for patients with sickle cell disease: A survey of transfusion service directors in the United States

2016 ◽  
Vol 54 (1) ◽  
pp. 158-162 ◽  
Author(s):  
Matthew S. Karafin ◽  
Arun K. Singavi ◽  
Mehraboon S. Irani ◽  
Kathleen E. Puca ◽  
Lisa Baumann Kreuziger ◽  
...  
Keyword(s):  
United States ◽  
Sickle Cell Disease ◽  
Sickle Cell ◽  
The United States ◽  
Red Cell ◽  
Cell Disease ◽  
Cell Storage

scholarly journals Genome editing using CRISPR-Cas9 to create the HPFH genotype in HSPCs: An approach for treating sickle cell disease and β-thalassemia

2016 ◽  
Vol 113 (38) ◽  
pp. 10661-10665 ◽  
Author(s):  
Lin Ye ◽  
Jiaming Wang ◽  
Yuting Tan ◽  
Ashley I. Beyer ◽  
Fei Xie ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Genome Editing ◽  
Sickle Cell ◽  
Globin Gene ◽  
Autologous Transplantation ◽  
Clinical Manifestations ◽  
Fetal Hemoglobin ◽  
Compound Heterozygous ◽  
Cell Disease ◽  
Hematopoietic Stem

Hereditary persistence of fetal hemoglobin (HPFH) is a condition in some individuals who have a high level of fetal hemoglobin throughout life. Individuals with compound heterozygous β-thalassemia or sickle cell disease (SCD) and HPFH have milder clinical manifestations. Using RNA-guided clustered regularly interspaced short palindromic repeats-associated Cas9 (CRISPR-Cas9) genome-editing technology, we deleted, in normal hematopoietic stem and progenitor cells (HSPCs), 13 kb of the β-globin locus to mimic the naturally occurring Sicilian HPFH mutation. The efficiency of targeting deletion reached 31% in cells with the delivery of both upstream and downstream breakpoint guide RNA (gRNA)-guided Staphylococcus aureus Cas9 nuclease (SaCas9). The erythroid colonies differentiated from HSPCs with HPFH deletion showed significantly higher γ-globin gene expression compared with the colonies without deletion. By T7 endonuclease 1 assay, we did not detect any off-target effects in the colonies with deletion. We propose that this strategy of using nonhomologous end joining (NHEJ) to modify the genome may provide an efficient approach toward the development of a safe autologous transplantation for patients with homozygous β-thalassemia and SCD.

scholarly journals Antimicrobial Resistance and Sickle Cell Protein Analysis in Invasive Non-Typhoidal Salmonella Isolated From Outpatient and Hospitalized Children Below 16 Years in Informal Settlements in Nairobi Kenya

2020 ◽  
Author(s):  
Susan Kavai ◽  
Cecilia Mbae ◽  
Celestine Wanjiku ◽  
Ronald Ngetich ◽  
Zillah Wakio ◽  
...  
Keyword(s):  
Sickle Cell Disease ◽  
Salmonella Typhimurium ◽  
Sickle Cell ◽  
Informal Settlements ◽  
The United States ◽  
Sub Saharan Africa ◽  
Cell Protein ◽  
Cell Disease ◽  
Resistance Phenotype ◽  
Stool Samples

Abstract Background: Invasive Non-typhoidal Salmonella (iNTS) disease continues to be a major public health problem, especially in sub Saharan Africa where incidence rates are 227 cases [range 152-341] per 100,000 population. Populations at risk of iNTS include adults with HIV infection, malnourished children, those with recent malaria or sickle-cell anaemia (SCA). Individuals with SCA are at an increased risk of invasive bacterial infections with the proportion of deaths from infection reported to be as high as 38% in the United States and 29% in Jamaica. In Kenya, iNTS disease is particularly a major challenge in poor informal settlements with infants and young children less than 5 years of age being the most affected; mortality rates can be 20-25% unless prompt treatment is administered. Methods Our study was conducted in 3 outpatient sites and 1 inpatient site, the outpatient sites were all located within Mukuru informal settlement, a densely populated slum, 15km East of Nairobi City. Blood and stool samples from children with fever alone and with fever and diarrhea were collected for processing for presence of iNTS using basic microbiology procedures. Dry blood spots were also taken and processed for sickle cell protein markers using High performance liquid chromatography (HPLC). Results A total of 22,246 blood and stool samples were collected from children < 16 years of age with fever/with or without diarrhea, for a period of 6 years and subjected to microbiological culture and detection of bacterial pathogens. Out of these 741 (3.3%) tested positive for Salmonella species. A total of 338/741(41%) NTS were isolated across all the sites; these consisted of 158/741(21%) Salmonella Enteritidis and 180/741 (24%) Salmonella Typhimurium. The most common resistance phenotype was ampicillin, cotrimoxazole and chloramphenicol (35.03%). We had 12/338 (3.6%) isolates (11 of them being Salmonella Typhimurium) that were ESBL producers conferring resistance to 3rd generation cephalosporins (Amp C β-lactamases) while only 0.3% were resistant to ciprofloxacin. A total of 118 (35.03%) isolates were MDR. Out of 2684 dry blood samples subjected to HPLC for investigation of sickle cell disease traits, 1820/2684 (67%) had normal hemoglobin (Hb AA/ Hb AF); (162/2684 (6%) tested positive for Sickle Cell Traits (Hb AS/Hb AFS); while 4/2684 (0.2%) tested positive for Sickle cell disease (Hb FS). Conclusion The high MDR resistance phenotype in iNTS isolates and emerging resistance to third generation cephalosporins is of great concern in management of iNTS in our settings. Sickle cell disease was not a major factor among children with iNTS disease and no significant association with iNTS was observed.

Newborn Screening for Sickle Cell Disease and Other Hemoglobinopathies

PEDIATRICS ◽  
1989 ◽  
Vol 83 (5) ◽  
pp. 813-814
Author(s):  
DORIS WETHERS ◽  
HOWARD PEARSON ◽  
MARILYN GASTON
Keyword(s):  
Sickle Cell Disease ◽  
Early Diagnosis ◽  
Sickle Cell ◽  
Sickle Cell Anemia ◽  
Case Fatality ◽  
The United States ◽  
Early Mortality ◽  
Cell Disease ◽  
Newborn Period ◽  
The Past

Hemoglobinopathies represent one of the major health problems in the United States and constitute the most common genetic disorders in some populations. Sickle cell disease (SS, SC, S-β-thalassemia) alone affects about one in 400 American black newborns, as well as persons of African, Mediterranean, Asian, Caribbean, Middle Eastern, and South and Central American origins. For the past 20 years, the medical profession has known that children with sickle cell anemia have an increased susceptibility to severe bacterial infection, particularly due to Streptococcus pneumoniae. The risk of major infection and death posed by this organism is greatest in the first 3 years of life and can occur as early as 3 months of age. In fact, this infection may be the first clinical manifestation of disease. The infection can be fulminant, progressing from the onset of fever to death in a matter of hours, and the case fatality rate is reported as high as 30%. In addition, acute splenic sequestration, another acute catastrophic event, contributes to early mortality in children with sickle cell anemia and may occur as early as 5 months of age. It has been proposed that early diagnosis to identify infants with major sickle hemoglobinopathies, who have a high risk of early mortality and morbidity, is essential to institute appropriate ongoing care and effective measures of prophylaxis and intervention. Early diagnosis of hemoglobinopathies should be in the newborn period. Even though the technology to screen infants in the newborn period has been available for the past 15 to 20 years, screening has not received widespread acceptance.

Haemoglobinopathies

2013 ◽  
pp. 1466-1470
Author(s):  
David Rees
Keyword(s):  
Bone Marrow ◽  
Sickle Cell Disease ◽  
Sickle Cell ◽  
Lupus Erythematosus ◽  
Single Gene ◽  
Globin Genes ◽  
Globin Chain ◽  
Cell Disease ◽  
Chain Synthesis ◽  
Marrow Expansion

Inherited abnormalities of the globin genes are the commonest single-gene disorders in the world and fall into two main groups: thalassaemias and sickle cell disease. Thalassaemias are due to quantitative defects in globin chain synthesis which cause variable anaemia and ineffective erythropoiesis. Thalassaemia was initially thought to be a disease of the bones due to uncontrolled bone marrow expansion causing bony distortion, although this is now unusual with appropriate blood transfusions. Osteopenia, often severe, is a feature of most patients with thalassaemia major and intermedia, caused by bone marrow expansion, iron overload, endocrinopathy, and iron chelation. Treatment with bisphosphonates is generally recommended. Other rheumatological manifestations include arthropathy associated with the use of the iron chelator deferiprone. Sickle cell disease involves a group of conditions caused by polymerization of the abnormal -globin chain, resulting in abnormal erythrocytes which cause vaso-occlusion, vasculopathy, and ischaemic tissue damage. The characteristic symptom is acute bone pain caused by vaso-occlusion; typical episodes require treatment with opiate analgesia and resolve spontaneously by 5 days with no lasting bone damage. The frequency of acute episodes varies widely between patients. The incidence of osteomyelitis is increased, particularly with salmonella, although it is much rarer than acute vaso-occlusion. Avascular necrosis can affect the hips, and less commonly the shoulders and knees. Coincidental rheumatological disease sometimes complicates the condition, particularly systemic lupus erythematosus (SLE) which is more prevalent in populations at increased risk of sickle cell disease.

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