The molecular genetic characteristics of a family with rare -88 C>G (HBB: c.-138 C>G) β-thalassemia gene mutation were studied using cohort study. The cohort study was conducted from June to August 2022 by Prenatal Diagnosis Center of Sanya Women and Children's Hospital Managed by Shanghai Children's Medical Center. The phenotype and genotype were analyzed by hematological cytoanalyzer, automatic electrophoretic analysis system, and next-generation sequencing (NGS). And then, Sanger sequencing was used to verify the rare gene results. The results showed that the proband, her father, her uncle and her younger male cousin had discrete microcytosis (MCV 70.1 fl, 71.9 fl, 73.1 fl and 76.6 fl, respectively) and hypochromia (MCH 21.5 pg,22.0 pg,22.6 pg and 23.5 pg, respectively), elevated hemoglobin A2 level (5.3%, 5.4%, 5.4% and 5.5%, respectively), slightly elevated or normal fetal hemoglobin (Hb F), but no anemia. The proband was identified to have co-inherited ɑ-thalassemia (Hb Westmead gene heterozygous mutation, ɑ^wsɑ/ɑɑ) and β-thalassemia with a rare -88 C>G (HBB: c.-138 C>G) heterozygous mutation (β^{-88 C>G}/β^N). Her mother had the same α-thalassemia as the proband. Her father, her uncle and her younger male cousin had the same rare -88 C>G heterozygous mutations as the proband. While her grandmother and younger brother were not carrier of thalassemia. In conclusion, 4 cases of rare -88 C>G(HBB:c.-138 C>G) heterozygous mutation had been detected in a Chinese family. Carriers of this beta-thalassemia are clinically asymptomatic. This study enriches the knowledge of the thalassemia mutation spectrum in Chinese people and provides valuable information for genetic counseling, prenatal diagnosis, and prevention of thalassemia, providing a scientific basis for improving the quality of birth population and preventing birth defects.
Female ; Humans ; Male ; alpha-Thalassemia/genetics* ; beta-Globins/genetics* ; beta-Thalassemia/diagnosis* ; China ; Cohort Studies ; Genotype ; Molecular Biology ; Mutation

OBJECTIVE: To provide a research basis for a safe and effective cell therapy for β-thalassemia through optimization of HS4 region of the third generation lentiviral vector for stable expression of β-globin. METHODS: The human β-globin HS4 region in the third generation lentiviral expression vector was optimized to construct the lenti-HBB, and the transcription and translation of β-globin gene were analyzed by RT-PCR and Western blot after the transduction of lenti-HBB in MEL cell line. Furthermore, the erythroid differentiation of CD34⁺ cells which were transduced lentiviral virus carrying human β-globin from normal human umbilical cord blood cells and peripheral blood cells of patients with β-thalassemia major were confirmed by colony formation assay, cell smear assay and flow cytometry. The safety and effectiveness of the optimized lenti-HBB were verified by NSG mouse in vivo test. RESULTS: The human β-globin was expressed stably in the MEL cells, and CD34⁺ cells from health umbilical cord blood as well as PBMC from patient with β-thalassemia major transduced with lenti-HBB could be differentiated to mature red blood cells. The β-globin expression and differentiation in CD34⁺ cells were demonstrated successfully in the NSG mouse for about 35 months after post-transplant. CONCLUSION Stable β-globin expression through the optimization of HS4 from CD34⁺ in the third generation lentiviral vector is safe and effective for patients with severe β-thalassemia and other β-globin abnormal diseases.
Animals ; Genetic Therapy ; Genetic Vectors ; Humans ; Lentivirus/genetics* ; Leukocytes, Mononuclear ; Mice ; beta-Globins/genetics* ; beta-Thalassemia/therapy*

OBJECTIVE: To investigate whether β-globin gene 3'UTR+101G>C (HBB:c.*233G>C) variant has genetic effect and provide basis for gene diagnosis and genetic counseling. METHOD: Whole blood cell analysis and capillary zone electrophoresis (CZE) were used to analyze the hematological indexes. The most frequent 23 mutations in southern Chinese individuals were routinely measured by PCR-flow fluorenscence immunmicrobeads assay. Sanger sequencing was used to detect the other variants of β-globin gene (HBB). RESULTS: In 463 cases, a total of 7 cases with HBB:c.*233G>C variant were detected, among them 4 cases carried other pathogenic variants of HBB gene (2 cases were in trans, 2 cases were in cis), who had typical hematological characteristics of mild β-thalassemia, and 3 cases also carried abnormal hemoglobin variation, but did not have hematological characteristics of β-thalassemia. CONCLUSION The study shows that HBB:c.*233G > C variant has no obvious genetic effect and should be a benign polymorphism.
3' Untranslated Regions ; Hemoglobins, Abnormal/genetics* ; Humans ; Mutation ; beta-Globins/genetics* ; beta-Thalassemia/genetics*

OBJECTIVE: To explore the application value of next generation sequencing (NGS) in preimplantation genetic diagnosis of α/β complex thalassemia couple. METHODS: The coding regions of α-globin genes (HBA1, HBA2) and β-globin gene (HBB) were selected as the target regions. The high-density and closely linked single nucleotide polymorphism (SNP) sites were selected as the genetic linkage markers in the upstream and downstream 2M regions of the gene. After NGS, the effective SNP sites were selected to construct the haplotype of the couple, and the risk chromosome of the mutation carried by the couple was determined. The NGS technology was used to sequence the variations of HBA1, HBA2 and HBB directly and construct haplotype linkage analysis for preimplantation genetic diagnosis. RESULTS: Direct sequencing and haplotype linkage analysis of HBA1, HBA2 and HBB showed that two of the six blastocysts were α/β complex thalassemia, one was β-thalassemia heterozygote, two were α-thalassemias heterozygotes, and one was intermediate α-thalassemia. A well-developed embryo underwent preimplantation genetic diagnosis was implanted into the mother's uterus, and a healthy infant was born at term. CONCLUSION Preimplantation genetic diagnosis can be carried out by NGS technology in α/β complex thalassemia couples, and abortion caused by aneuploid embryo selection can be avoided.
Female ; High-Throughput Nucleotide Sequencing ; Humans ; Mutation ; Pregnancy ; Preimplantation Diagnosis ; alpha-Thalassemia ; beta-Globins/genetics* ; beta-Thalassemia/genetics*

OBJECTIVE: To study the hematologic and molecular features of 14 patients with hemoglobin (Hb) variants, so as to provide reference data for its laboratory screening. METHODS: A total of 1 029 samples were screened by high performance liquid chromatography (HPLC) on the Bio-Rad VariantⅡHPLC system. GAP-PCR and reverse dot blot (RDB) were used to detect common mutation of α and β globin gene in Chinese. DNA sequencing for α and β globin gene was simultaneously performed in samples with abnormal spectrum peak and negative thalassemia gene. RESULTS: In 1 029 samples, 10 types of structural Hb variants were detected in14 cases (1.36%), including 1 case of Hb E / β- thalassemia, 1 case of Hb E /α- thalassemia (HbH disease), 2 cases of HbG-Taipei, 2 cases of Hb Q-Thailand, 2 cases of Hb Youngstown, 1 case of Hb Guangzhou-Hangzhou, 1 case of Hb M-Boston, 1 case of Hb G-Siriraj, 1 case of Hb J-Baltimore, 1 case of Hb J-Sicilia and 1 case of Hb Tamano. CONCLUSION The occurrence of abnormal structural Hb variants with many genotypes in Shanghai is unique. Except for Hb E, Hb Youngstown, and Hb M-Boston, other types of heterozygous are normal in phenotypes, and symptoms such as hemolysis and anemia often occur when other diseases are combined.
China ; Genotype ; Hemoglobins, Abnormal/genetics* ; Humans ; Phenotype ; alpha-Thalassemia ; beta-Globins/genetics*

β-thalassemia is a monogenetic inherited hemolytic anemia, which results in a series of pathophysiological changes due to partial or complete inhibition of the synthesis of β-globin chain. The curative therapy for this disease is to reconstitute hematopoiesis, and transplantation with genetically modified autologous hematopoietic stem cells can avoid the major difficulties of traditional allogeneic hematopoietic stem cell transplantation，such as HLA matching and immune rejection. β-thalassemia gene therapy strategies mainly include gene integration and genome editing. The former relies on the development of lentiviral vectors and adds a fully functional HBB gene to the chromosome; the latter rapidly develops with the research of specific nuclease which can repair the HBB gene in situ. In this review, the latest progress of the two strategies in gene therapy of β-thalassemia is summarized.
Gene Editing ; Genetic Therapy ; Genetic Vectors ; Humans ; beta-Globins/genetics* ; beta-Thalassemia/therapy*

OBJECTIVE: To determine the composition and distribution of beta-thalassemia-associated genotypes in Liuzhou area of Guangxi, China. METHODS: From January to December 2017, 13 847 individuals who came for premarital examination, maternity examination or health check were recruited with informed consent. The subjects were analyzed by reverse dot blotting (RDB) for 17 common beta-thalassemia-associated variants among the Chinese population. Individuals with inconsistent results by blood test, electrophoresis, and RDB were subjected to Sanger sequencing to detect rare variants of the beta globin gene. RESULTS: In total 2098 individuals were found to harbor beta-thalassemia-associated variants, which included 2075 heterozygotes (98.90%), 12 compound heterozygotes (0.57%) and 11 homozygotes (0.52%). CD41-42 (48.43%) and CD17 (31.45%) were the most common variants. Three hundred and thirty eight-individuals were found to also carry heterozygous variants of the alpha globin gene, with the most common types being --SEA/aa, -a3.7/aa, aCSa/aa, -a4.2/aa. Through Sanger sequencing, rare genotypes such as beta-32/betaN, betaCD41-42/betaIVS-II-5 and betaCD30/betaN were detected. CONCLUSION Liuzhou area has a high incidence of beta-thalassemia, but with a complex variant spectrum and clinical phenotypes different from other regions. Genetic counseling and prenatal diagnosis for the carrier population is crucial for the reduction of the related birth defects. Our result may provide valuable information for the prevention and control of beta-thalassemia in this area.
China ; Female ; Genetic Counseling ; Genetic Variation ; Genotype ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis ; alpha-Globins ; genetics ; beta-Globins ; genetics ; beta-Thalassemia ; diagnosis ; genetics

OBJECTIVETo analyze the hematological and genetic characteristics of unstable hemoglobin Rush (Hb Rush) and compound heterozygote of Hb Rush and thalassemia.

METHODSPeripheral blood samples and genomic DNA from three patients (including two ethnic Dai and one Han Chinese) with anemia of undetermined origin were collected. Hematological phenotypes of these patients were determined through red blood cell analysis and hemoglobin electrophoresis. Genotypes of alpha- and beta-globin genes, -158 XmnⅠ polymorphic site ofγ promoter region, and haplotypes of 7 polymorphic restriction sites in the beta-globin gene cluster were determined using PCR-based methods and DNA sequencing.

RESULTSAll patients have presented hypochromic microcytic anemia and hemoglobin fraction with significant increased measurement (30.5%-59.2%) in the region of fetal hemoglobin during alkaline medium electrophoresis. DNA analysis suggested that all patients have carried mutations leading to the unstable hemoglobin Rush (HBB codon 101, GAG>CAG, Glu>Gln). Two of them were compound heterozygotes of Hb Rush and thalassemia mutations of -α,CD17 and Hb E, respectively. Hb Rush mutation was associated with various haplotypes of the β-globin gene cluster. No significant association was found between increased abnormal hemoglobin fraction in the region of Hb F and the polymorphism ofγ promoter or large deletion of the beta-globin gene cluster.

CONCLUSIONThis study has confirmed the distribution of Hb Rush among various Chinese populations and is the third report of its kind. Hb Rush can result in increased measurement of hemoglobin fraction in the region of fetal hemoglobin (Hb F) during routine hemoglobin electrophoresis under alkaline condition. Hb Rush heterozygote alone can lead to hypochromic microcytic anemia and thalassemia-like phenotype. Prenatal diagnosis of Hb Rush is necessary for carriers.

Adult ; Base Sequence ; Blood Protein Electrophoresis ; methods ; Female ; Fetal Hemoglobin ; genetics ; metabolism ; Genotype ; Haplotypes ; Hemoglobins, Abnormal ; genetics ; metabolism ; Heterozygote ; Humans ; Infant ; Mutation ; Phenotype ; Polymorphism, Genetic ; Sequence Analysis, DNA ; methods ; Thalassemia ; blood ; diagnosis ; genetics ; Young Adult ; alpha-Globins ; genetics ; metabolism ; beta-Globins ; genetics ; metabolism

OBJECTIVETo identify a novel hemoglobinopathy applied by direct sequencing and clone sequencing.

METHODSEDTA anticoagulated blood of proband and his parents were analyzed by hematology analyzers and Capillarys hemoglobin electrophoresis (CE). Then thalassemia genetypes were screened by gap-PCR and reverse dot blot (RDB). Proband was suspected with abnormal hemoglobin combine alpha beta compound thalassemia. The mutation of beta-globin was identified by direct sequencing and clone sequencing.

RESULTSHb analysis showed that probands Hb A2 variant was eluted in Z (C) zone and his father's in Z (A2) zone on CE,and proband's mother elevated HbA2 of 4.6%. Screened by RDB, the proband was CD71-72(+A) homozygote and showed the mismatch with his parents. Through direct sequencing and clone sequencing, we deduced that our proband inherited the mutations of HBB c.[219T>A;220G>T] from his father and inherited the Southeast-Asian deletion and HBB c.216-217insA from his mother.

CONCLUSIONA novel double heterozygote of HBB c.[219T>A; 220G>T] was identified in south China. This mutation enriches the beta-thalassemia gene mutation spectrum in Chinese population.

Asian Continental Ancestry Group ; genetics ; Child, Preschool ; Hemoglobins ; genetics ; Hemoglobins, Abnormal ; genetics ; Heterozygote ; Humans ; Male ; Mutation ; genetics ; Pedigree ; Thalassemia ; genetics ; beta-Globins ; genetics

OBJECTIVETo detect rare types of thalassemia mutations among southern Chinese population.

METHODSPeripheral blood samples from 327 patients from various regions of southern China were collected. The patients were suspected as rare-type thalassemia for their inconsistency between hematological phenotypes and results of routine mutation screening. The samples were further analyzed with GAP-PCR and DNA sequencing.

RESULTSOne hundred and eight cases were diagnosed as rare types of thalassemia. Among whom 10 rare α-globin gene mutations including --THAI, HKα, αααanti3.7, αααanti4.2, -α2.8, -α27.6, CD74 GAC>CAC (Hb Q-Thailand), CD30 (-GAG), CD31 AGG>AAG and CD118 (+TCA), and 12 rare β-globin gene mutations including CD37 TGG>TAG, CD39 CAG>TAG/CD39 CAG>TAG, β II-2 (-T), -90(C>T), -31(A>C), -88(C>T), CD7(-A), CD138(+T), CD89-93 (--AGTGAGCTGCACTG), CD54-58 (-TATGGGCAACCCT), Chinese G γ +(A γδβ)0 and Vietnamese HPFH (HPFH-6) were identified. -88(C>T) (HBB: c.-138C>T) and CD39 CAG>TAG (HBB: c.118C>T) were discovered for the first time in Chinese population. CD7(-A) (HBB: c.23delA) and CD138(+T) (HBB: c.416_417insT) were new types of β-globin gene mutations.

CONCLUSIONThe present study have enriched the mutation spectrum of thalassemia in southern China, which has provided necessary information for its diagnosis.

Humans ; Mutation ; Thalassemia ; genetics ; alpha-Globins ; genetics ; beta-Globins ; genetics