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Molecular Genetics & Genomic Medicine Jan 2024Thalassemia is a common genetic disorder in southwestern China, and an increasing number of cases from eastern China have been recently reported. Here, we developed a...
BACKGROUND
Thalassemia is a common genetic disorder in southwestern China, and an increasing number of cases from eastern China have been recently reported. Here, we developed a rapid, convenient, and accurate assay to evaluate the mutation spectrum of thalassemia in eastern China.
METHODS
A carrier screening assay for 61 hotspot variants among HBA1/HBA2 and HBB (OMIM: 141800, 141850, and 141900) genes was developed by SNaPshot/high-throughput ligation-dependent probe amplification (HLPA) technology. We used this assay to detect the mutation spectrum of thalassemia in individuals from eastern China and compared with the data collected from literatures focused on southern and northern China for variant distribution.
RESULTS
Among 4276 tested individuals, 2.62% (112/4276) were α-thalassemia carriers, with 90 carrying one deletion or mutation and 22 carrying two deletions. 0.40% (17/4276) were β-thalassemia carriers, and the most common variant of β-thalassemia was c.126_129delCTTT (29.41%) followed by c.316-197C>T (23.53%). The genotype distribution in our study was similar to those from southern China populations.
CONCLUSION
The Chinese population from different regions presented comparable mutation spectrum of thalassemia, and the SNaPshot/HLPA technique may serve as a capable assay for a routine genetic test in clinical practice with its accurate, rapid, and inexpensive advantage.
Topics: Adult; Pregnancy; Female; Humans; beta-Thalassemia; Multiplex Polymerase Chain Reaction; alpha-Thalassemia; Mutation; Genotype
PubMed: 38112059
DOI: 10.1002/mgg3.2344 -
BioRxiv : the Preprint Server For... Nov 2023In regions where reads don't align well to a reference, it is generally difficult to characterize structural variation using short read sequencing. Here, we utilize...
In regions where reads don't align well to a reference, it is generally difficult to characterize structural variation using short read sequencing. Here, we utilize machine learning classifiers and short sequence reads to genotype structural variants in the alpha globin locus on chromosome 16, a medically-relevant region that is challenging to genotype in individuals. Using models trained only with simulated data, we accurately genotype two hard-to-distinguish deletions in two separate human cohorts. Furthermore, population allele frequencies produced by our methods across a wide set of ancestries agree more closely with previously-determined frequencies than those obtained using currently available genotyping software.
PubMed: 38076833
DOI: 10.1101/2023.11.27.568683 -
Frontiers in Genetics 2023This study aimed to evaluate the feasibility and necessity of using fluorescence Gap-polymerase chain reaction combined with haplotype analysis in preimplantation...
This study aimed to evaluate the feasibility and necessity of using fluorescence Gap-polymerase chain reaction combined with haplotype analysis in preimplantation genetic testing for SEA-type α-thalassemia. A total of 26 preimplantation genetic testing biopsy cycles were performed in 25 families from June 2021 to February 2022. All couples were carriers of SEA-type α-thalassemia. Fluorescent Gap-polymerase chain reaction was used for detecting fragment deletion. Subsequently, according to the results of polymerase chain reaction, reference embryos were identified to establish haplotype using single nucleotide polymorphism array, and aneuploidy was screened simultaneously. In cases wherein the polymerase chain reaction results were inconsistent with the haplotype results, the reasons were investigated, either by retest of the biopsied samples or rebiopsy of the embryo. Among the 172 embryos, 162 had consistent results when tested using both methods, resulting in a consistency rate of 94.2%. Conversely, 10 embryos had inconsistent results, mainly due to chromosome 16 aneuploidy ( = 7), allele dropout in Gap-polymerase chain reaction ( = 2), or incorrect haplotype due to poor sample amplification quality ( = 1). The clinical pregnancy rate of each frozen-thawed embryo transfer was 57.7% (15/26). Six families underwent prenatal diagnosis, which confirmed the results of preimplantation genetic testing. Fluorescent Gap-polymerase chain reaction combined with haplotype analysis is feasible and necessary for SEA-type α-thalassemia preimplantation genetic testing.
PubMed: 38075678
DOI: 10.3389/fgene.2023.1248358 -
EJHaem Nov 2023Haemoglobin (Hb) G-Makassar is a rare Hb variant. It presents a diagnostic challenge as it imitates sickle Hb (Hb S) in standard electrophoresis and high-performance...
Haemoglobin (Hb) G-Makassar is a rare Hb variant. It presents a diagnostic challenge as it imitates sickle Hb (Hb S) in standard electrophoresis and high-performance liquid chromatography assays requiring DNA analysis to confirm diagnosis. Both have point mutations in codon 6, exon 1 in the β-globin () gene with different pathogenicities. This study describes the clinical phenotype, haematology and genotype of Hb G-Makassar. Clinical and laboratory data of 38 cases of Hb G-Makassar over 8 years were analysed. Hb G-Makassar was confirmed by a direct sequencing of gene and co-inheritance of α-thalassaemia determined through multiplex gap-PCR and multiplex Amplification Refractory Mutation System polymerase chain reaction. All cases were Malays, predominantly from Terengganu ( = 20, 52.6%). There were 14 (36.8%) males and 24 (63.2%) females with median age of 25 years. Majority ( = 33, 86.8%) had features of thalassaemia trait with mean ± SD for Hb, mean cell volume (MCV) and mean cell haemoglobin (MCH) as 13.21 g/dL ± 1.69, 73.06 ± 4.48 fL and 24.71 ± 1.82 pg, respectively. None had evidence of haemolysis or thromboembolic complications. Six genotypes were identified; ß/ß,αα/αα ( = 19, 50.0%), ß/ß,αα/αα ( = 4, 10.5%), ß/ß,αα/αα ( = 1, 2.6%), ß/ß,αα/-α ( = 11, 28.9%), ß/ß,αα/αα ( = 2, 5.3%) and ß/ß,αα/- ( = 1, 2.6%). The ß/ß,αα/αα showed that features of thalassaemia trait with mean ± SD for Hb, MCV and MCH were 13.74 g/dL ± 2.40, 76.18 ± 6.02 fL and 25.79 ± 2.41 pg, respectively. This is the largest study reporting a significant number of Hb G-Makassar in Malaysia. Although the mutation is similar to Hb S, the phenotype is benign.
PubMed: 38024609
DOI: 10.1002/jha2.750 -
International Journal of Molecular... Nov 2023The dADD1 and dXNP proteins are orthologues of the ADD and SNF2 domains of the vertebrate ATRX (Alpha-Thalassemia with mental Retardation X-related) protein. ATRX plays... (Review)
Review
The dADD1 and dXNP proteins are orthologues of the ADD and SNF2 domains of the vertebrate ATRX (Alpha-Thalassemia with mental Retardation X-related) protein. ATRX plays a role in general molecular processes, such as regulating chromatin status and gene expression, while dADD1 and dXNP have similar functions in the genome. Both ATRX and dADD1/dXNP interact with various protein partners and participate in various regulatory complexes. Disruption of ATRX expression in humans leads to the development of α-thalassemia and cancer, especially glioma. However, the mechanisms that allow ATRX to regulate various cellular processes are poorly understood. Studying the functioning of dADD1/dXNP in the model may contribute to understanding the mechanisms underlying the multifunctional action of ATRX and its connection with various cellular processes. This review provides a brief overview of the currently available information in mammals and regarding the roles of ATRX, dXNP, and dADD1. It discusses possible mechanisms of action of complexes involving these proteins.
Topics: Animals; Humans; alpha-Thalassemia; Chromatin; DNA Helicases; Drosophila; Drosophila melanogaster; Drosophila Proteins; Mammals; X-linked Nuclear Protein
PubMed: 38003676
DOI: 10.3390/ijms242216486 -
The Journal of Invasive Cardiology Nov 2023We present a 73-year-old female with history of rheumatic heart disease status post-mechanical mitral valve on warfarin, valvular atrial fibrillation, and alpha...
We present a 73-year-old female with history of rheumatic heart disease status post-mechanical mitral valve on warfarin, valvular atrial fibrillation, and alpha thalassemia who was admitted to an outside hospital with anterior ST-segment myocardial infarction. Coronary angiogram showed occluded left anterior descending artery (LAD) with acute thrombus status post-thrombectomy and balloon angioplasty.
Topics: Female; Humans; Aged; Shock, Cardiogenic; Atrial Fibrillation; Mitral Valve; Heart Diseases; Thrombosis; Thrombectomy
PubMed: 37992325
DOI: 10.25270/jic/23.00154 -
Molecular Genetics & Genomic Medicine Jan 2024Acid ceramidase (ACDase) deficiency is an ultrarare autosomal recessive lysosomal disorder caused by pathogenic N-acylsphingosine amidohydrolase (ASAH1) variants. It...
BACKGROUND
Acid ceramidase (ACDase) deficiency is an ultrarare autosomal recessive lysosomal disorder caused by pathogenic N-acylsphingosine amidohydrolase (ASAH1) variants. It presents with either Farber disease (FD) or spinal muscular atrophy with progressive myoclonic epilepsy (SMA-PME).
OBJECTIVE
The study aims to identify a novel splice site variant in a hydrops fetus that causes ASAH1-related disorder, aid genetic counseling, and accurate prenatal diagnosis.
METHODS
We report a case of hydrops fetalis with a novel homozygous mutation in ASAH1 inherited from non-consanguineous parents. We performed copy number variation sequencing (CNV-Seq) and whole exome sequencing (WES) on the fetus and family, respectively. Minigene splicing analyses were conducted to confirm the pathogenic variants.
RESULTS
WES data revealed a splice site variant of the ASAH1 (c.458-2A>T), which was predicted to affect RNA splicing. Minigene splicing analyses found that the c.458-2A>T variant abolished the canonical splicing of intron 6, thereby activating two cryptic splicing products (c.456_458ins56bp and c.458_503del).
CONCLUSIONS
Overall, we identified a novel splice site variant in the mutational spectrum of ASAH1 and its aberrant effect on splicing. These findings highlight the importance of ultrasonic manifestation and family history of fetal hydrops during ASAH1-related disorders and could also aid genetic counseling and accurate prenatal diagnosis. To the best of our knowledge, this is the shortest-lived account of ASAH1-related disorders in utero with severe hydrops fetalis.
Topics: Female; Pregnancy; Humans; Muscular Atrophy, Spinal; DNA Copy Number Variations; Hydrops Fetalis; Mutation; Introns; Acid Ceramidase
PubMed: 37962265
DOI: 10.1002/mgg3.2317 -
Thrombosis Journal Nov 2023Alpha-thalassemia (α-thalassemia) is one of the most common monogenic diseases in Saudi Arabia and is associated with significant morbidity. Premarital testing programs...
BACKGROUND
Alpha-thalassemia (α-thalassemia) is one of the most common monogenic diseases in Saudi Arabia and is associated with significant morbidity. Premarital testing programs in Saudi Arabia reduce the burden of hemoglobinopathy disorders, and ongoing monitoring is required. We aimed to explore the molecular nature of α-globin genes and identify the most common genotypes and regions with a high risk of α-thalassemia in Saudi Arabia.
METHODS
This retrospective study was conducted between January 2021 and December 2022. Six hundred twenty-five samples from patients with microcytic hypochromic anemia in Saudi Arabia were analyzed using reverse dot blot hybridization (RDBH)-based multiplex-PCR, which screens for the known 21 mutations of α-globin genes.
RESULTS
Seven mutations in the α-globin gene were identified in 88.96% (556) patients. The most frequent abnormality of a-globin genes was -α (62.3%), followed by α2 (20.7%) and α2 polyA-1 (α2) (14.1%). Interestingly, α2 polyA-2 (α2) was identified in Saudi and presented with -MED, causing Haemoglobin H disease. The incidence of α-thalassemia in Saudi Arabia's cities showed significant differences (P = 0.004). Jeddah City had the highest percentage of cases (25%), followed by Makkah (23%), Taif (13.3%), and Al-Ahassa (12.4%).
CONCLUSION
The study provides current knowledge about the molecular nature of α- thalassemia, highlights the common genotypes that could contribute to disease occurrence in the Saudi population, and sheds light on Saudi regions with a high incidence. It also recommends further studies in a larger population and with differently composed molecular assays to verify these findings.
PubMed: 37950286
DOI: 10.1186/s12959-023-00560-w -
Experimental Cell Research Dec 2023The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causative of the ongoing coronavirus disease 2019 (COVID-19) pandemic. The SARS-CoV-2 Spike protein...
The anti-SARS-CoV-2 BNT162b2 vaccine suppresses mithramycin-induced erythroid differentiation and expression of embryo-fetal globin genes in human erythroleukemia K562 cells.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is causative of the ongoing coronavirus disease 2019 (COVID-19) pandemic. The SARS-CoV-2 Spike protein (S-protein) plays an important role in the early phase of SARS-CoV-2 infection through efficient interaction with ACE2. The S-protein is produced by RNA-based COVID-19 vaccines, that were fundamental for the reduction of the viral spread within the population and the clinical severity of COVID-19. However, the S-protein has been hypothesized to be responsible for damaging cells of several tissues and for some important side effects of RNA-based COVID-19 vaccines. Considering the impact of COVID-19 and SARS-CoV-2 infection on the hematopoietic system, the aim of this study was to verify the effect of the BNT162b2 vaccine on erythroid differentiation of the human K562 cell line, that has been in the past intensively studied as a model system mimicking some steps of erythropoiesis. In this context, we focused on hemoglobin production and induced expression of embryo-fetal globin genes, that are among the most important features of K562 erythroid differentiation. We found that the BNT162b2 vaccine suppresses mithramycin-induced erythroid differentiation of K562 cells. Reverse-transcription-qPCR and Western blotting assays demonstrated that suppression of erythroid differentiation was associated with sharp inhibition of the expression of α-globin and γ-globin mRNA accumulation. Inhibition of accumulation of ζ-globin and ε-globin mRNAs was also observed. In addition, we provide in silico studies suggesting a direct interaction between SARS-CoV-2 Spike protein and Hb Portland, that is the major hemoglobin produced by K562 cells. This study thus provides information suggesting the need of great attention on possible alteration of hematopoietic parameters following SARS-CoV-2 infection and/or COVID-19 vaccination.
Topics: Humans; K562 Cells; Plicamycin; COVID-19 Vaccines; BNT162 Vaccine; Leukemia, Erythroblastic, Acute; COVID-19; SARS-CoV-2; Hemoglobins; RNA, Messenger; Erythroid Cells
PubMed: 37944576
DOI: 10.1016/j.yexcr.2023.113853 -
PloS One 2023Regions with a high prevalence of α-thalassemia (α-thal) require simple, rapid, and accurate tests for carrier screening and prenatal diagnosis. Diagnosis of multiple...
Regions with a high prevalence of α-thalassemia (α-thal) require simple, rapid, and accurate tests for carrier screening and prenatal diagnosis. Diagnosis of multiple deletions in a single tube is necessary to clearly identify individuals with α0-thalassemia in the routine setting, especially in at-risk couples. Therefore, we aimed to develop a single-tube multiplex real-time PCR with EvaGreen and high-resolution melting (HRM) analysis for the identification of α0-thalassemia Southeast Asian (SEA), Thai and Chiang Rai (CR) type deletions. The results of the HRM analysis indicated that the amplified fragments from α0-thal--CR,--THAI,--SEA, and the wild-type α-globin gene had specific peak heights at mean melting temperature (Tm) values of 85.40°C, 86.50°C, 87.65°C, and 91.04°C, respectively. The frequencies of α0-thal--SEA,--THAI,--CR obtained from routine testing in 2,135 samples were 17.89%, 0.19% and 0.19%, respectively. This method would be useful for preventing Hb Bart's hydrops fetalis. Detection of multiple deletions in a single run is cost-effective, highly accurate and timesaving. This technique could enable wider α-thalassemia diagnosis in high prevalence areas and served as an example for thalassemia routine setting.
Topics: Pregnancy; Female; Humans; alpha-Thalassemia; Thailand; Real-Time Polymerase Chain Reaction; Southeast Asian People; Hydrops Fetalis; Prenatal Diagnosis; Hemoglobins, Abnormal
PubMed: 37930985
DOI: 10.1371/journal.pone.0293838