Causes of Abnormal Hemoglobin Electrophoresis / 中国实验血液学杂志

OBJECTIVE@#To investigate the possible causes of abnormal hemoglobin electrophoresis results.@*METHODS@#The hemoglobin electrophoresis results of 5 696 patients in the First Affiliated Hospital of Chengdu Medical College from September 2018 to July 2021 were collected, and the abnormal results and clinical significance were analyzed.@*RESULTS@#The results of 486 patients (accounting for 8.53%) were abnormal, of which 300 cases had increased HbA2, 135 cases had decreased HbA2, 44 cases had increased F alone, and 7 cases had abnormal hemoglobin bands. Among the 486 patients, 246 patients were thalassemia gene positive (the positive rate was 50.62%), including 29 cases of α thalassemia, 208 cases of β thalassemia and 9 cases of αβ thalassemia. Among the patients with elevated HbA2, 68.67% were detected β thalassemia, 3.00% αβ thalassemia, 9.33% were suspected to be caused by macrocytosis, 6.33% by thyroid dysfunction, and 12.67% by uncertainty of the method. Among the patients with reduced HbA2, 21.48% were detected α thalassemia, 60.00% iron deficiency anemia, 8.15% were suspected to be caused by thyroid dysfunction, and 10.37% by uncertainty of the method. Among the patients with elevated F alone, the results of thalassemia gene detection were negative, 40.91% of them were suspected to be caused by macrocytosis, 27.27% by hereditary persistence of fetal hemoglobin, 29.55% by special physiological condition of pregnant women, and 2.27% by hyperthyroidism. Abnormal hemoglobin bands were detected in 7 patients, including 4 cases of hemoglobin D, 2 cases of hemoglobin E, and 1 case of hemoglobin J.@*CONCLUSION@#Thalassemia, iron deficiency anemia, macrocytosis such as megaloblastic anemia and non-severe aplastic anemia, thyroid dysfunction, hereditary persistence of fetal hemoglobin, abnormal hemoglobin diseases, the uncertainty of the method are all important causes of abnormal hemoglobin electrophoresis results. In clinical work, the patient's indicators should be comprehensively analyzed to determine the possible cause.

Genotype and Phenotype of α-Thalassemia Fusion Gene in Huadu District of Guangzhou, Guangdong Province of China / 中国实验血液学杂志

OBJECTIVE@#To explore the carrier rate, genotype and phenotype of α-thalassemia fusion gene in Huadu district of Guangzhou, Guangdong province of China, and provide data reference for the prevention and control of thalassemia.@*METHODS@#A total of 10 769 samples who were screened for thalassemia in Maternal and Child Health Hospital of Huadu District from July 2019 to November 2020 were analyzed retrospectively. Blood cell analysis and hemoglobin (Hb) electrophoresis were performed. Thalassemia genes were analyzed by gap-PCR and PCR-reverse dot blot hybridization (PCR-RDB).@*RESULTS@#A total of 9 cases with α-thalassemia fusion gene were detected in 10 769 samples (0.08%). There were 7 cases with fusion gene heterozygote, 1 case with compound of α-thalassemia fusion gene and Hb G-Honolulu, 1 case with compound of α-thalassemia fusion gene and Hb QS. The MCV results of 4 samples of blood cell analysis were within the reference range, the Hb A2 value of 1 case was decreased, and there were no other abnormalities found.@*CONCLUSION@#The α-thalassemia fusion gene is common in Huadu district of Guangzhou, and heterozygotes are more common, and current screening methods easily lead to misdiagnosis.

Epidemiological Survey of Hemoglobinopathies Based on Next-Generation Sequencing Platform in Hunan Province, China / 生物医学与环境科学（英文）

OBJECTIVE@#This study was aimed at investigating the carrier rate of, and molecular variation in, α- and β-globin gene mutations in Hunan Province.@*METHODS@#We recruited 25,946 individuals attending premarital screening from 42 districts and counties in all 14 cities of Hunan Province. Hematological screening was performed, and molecular parameters were assessed.@*RESULTS@#The overall carrier rate of thalassemia was 7.1%, including 4.83% for α-thalassemia, 2.15% for β-thalassemia, and 0.12% for both α- and β-thalassemia. The highest carrier rate of thalassemia was in Yongzhou (14.57%). The most abundant genotype of α-thalassemia and β-thalassemia was -α 3.7/αα (50.23%) and β IVS-II-654/β N (28.23%), respectively. Four α-globin mutations [CD108 (ACC>AAC), CAP +29 (G>C), Hb Agrinio and Hb Cervantes] and six β-globin mutations [CAP +8 (C>T), IVS-II-848 (C>T), -56 (G>C), beta nt-77 (G>C), codon 20/21 (-TGGA) and Hb Knossos] had not previously been identified in China. Furthermore, this study provides the first report of the carrier rates of abnormal hemoglobin variants and α-globin triplication in Hunan Province, which were 0.49% and 1.99%, respectively.@*CONCLUSION@#Our study demonstrates the high complexity and diversity of thalassemia gene mutations in the Hunan population. The results should facilitate genetic counselling and the prevention of severe thalassemia in this region.

Molecular genetic characteristics of a family which coinheritance of rare-88 C>G (HBB:c.-138 C>G) β-thalassemia mutation with α-thalassemia and review of the literature / 中华预防医学杂志

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, ɑwsɑ/ɑɑ) and β-thalassemia with a rare -88 C>G (HBB: c.-138 C>G) heterozygous mutation (β-88 C>G/βN). 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.

Thalassemia, a human blood disorder / Talassemia, uma doença do sangue humano

A group of inherited blood defects is known as Thalassemia is among the world's most prevalent hemoglobinopathies. Thalassemias are of two types such as Alpha and Beta Thalassemia. The cause of these defects is gene mutations leading to low levels and/or malfunctioning α and β globin proteins, respectively. In some cases, one of these proteins may be completely absent. α and β globin chains form a globin fold or pocket for heme (Fe++) attachment to carry oxygen. Genes for alpha and beta-globin proteins are present in the form of a cluster on chromosome 16 and 11, respectively. Different globin genes are used at different stages in the life course. During embryonic and fetal developmental stages, γ globin proteins partner with α globin and are later replaced by β globin protein. Globin chain imbalances result in hemolysis and impede erythropoiesis. Individuals showing mild symptoms include carriers of alpha thalassemia or the people bearing alpha or beta-thalassemia trait. Alpha thalassemia causes conditions like hemolytic anemia or fatal hydrops fetalis depending upon the severity of the disease. Beta thalassemia major results in hemolytic anemia, growth retardation, and skeletal aberrations in early childhood. Children affected by this disorder need regular blood transfusions throughout their lives. Patients that depend on blood transfusion usually develop iron overload that causes other complications in the body systems like renal or hepatic impairment therefore, thalassemias are now categorized as a syndrome. The only cure for Thalassemias would be a bone marrow transplant, or gene therapy with currently no significant success rate. A thorough understanding of the molecular basis of this syndrome may provide novel insights and ideas for its treatment, as scientists have still been unable to find a permanent cure for this deadly disease after more than 87 years since it is first described in 1925.

Um grupo de defeitos sanguíneos hereditários é conhecido como talassemia e está entre as hemoglobinopatias mais prevalentes do mundo. As talassemias são de dois tipos, como talassemia alfa e beta. As causas desses defeitos são as mutações genéticas que levam a níveis baixos e/ou proteínas de globina com mau funcionamento, respectivamente. Em alguns casos, uma dessas proteínas pode estar completamente ausente. As cadeias de globina α e β formam uma dobra ou bolsa de globina para a fixação de heme (Fe ++) para transportar oxigênio. Os genes das proteínas alfa e beta globina estão presentes na forma de um cluster nos cromossomos 16 e 11, respectivamente. Diferentes genes de globina são usados em diferentes estágios do curso de vida. Durante os estágios de desenvolvimento embrionário e fetal, as proteínas γ globina se associam à α globina e, posteriormente, são substituídas pela proteína β globina. Os desequilíbrios da cadeia de globina resultam em hemólise e impedem a eritropoiese. Indivíduos que apresentam sintomas leves incluem portadores de talassemia alfa ou as pessoas com traços de talassemia alfa ou beta. A talassemia alfa causa condições como anemia hemolítica ou hidropsia fetal fatal, dependendo da gravidade da doença. A beta talassemia principal resulta em anemia hemolítica, retardo de crescimento e aberrações esqueléticas na primeira infância. As crianças afetadas por esse distúrbio precisam de transfusões de sangue regulares ao longo da vida. Os pacientes que dependem de transfusão de sangue geralmente desenvolvem sobrecarga de ferro que causa outras complicações nos sistemas do corpo, como insuficiência renal ou hepática, portanto as talassemias agora são classificadas como uma síndrome. A única cura para as talassemias seria um transplante de medula óssea ou terapia genética sem atualmente uma taxa de sucesso significativa. Uma compreensão completa da base molecular dessa síndrome pode fornecer novos insights e ideias para seu tratamento, [...].

Thalassemia Gene Detection Results and Application Value of Hematological Indexes Among Pregnant Women in Xindu District of Chengdu City / 中国实验血液学杂志

OBJECTIVE@#To analyze the genotype characteristics of α- and β-thalassemia and the diagnostic value of hematological indexes in pregnant women in Xindu District of Chengdu.@*METHODS@#The blood routine parameters(MCV) <80 fl and (or) (MCH) <27 pg and hemoglobin electrophoresis were used to screen the pregnant women, PCR-reverse dot blot hybridization(PCR-RDB) technique was used to detect the common α- and β-thalassemia gene types in the primary screening positive population. The husbands of the diagnosed pregnant women were recalled for gene testing, and the highly suspected patients were checked by gene sequencing.@*RESULTS@#Among the 7 049 pregnant women, 1 740(24.68%) cases were positive for primary screening. 180 patients were diagnosed as thalassemia gene positive, among them, 94 cases (52.22%) of α-thalassemia were detected and six genotypes were found, in which --SEA /αα genotype was the highest (58 cases, 61.70%); 82 cases (45.56%) of β-thalassemia were detected and ten genotypes were found while CD41-42/N and CD17/N genotypes were the most common; there were 4 cases(2.22%) with α combined with β-thalassemia. Through clinical follow-up survey, there were 4 couples with the same type of thalassemia, one of them was induced labor after diagnosis of hemoglobin H disease. Receiver operating curve (ROC curve) was used to analyze the diagnostic value of hematological parameters in thalassemia positive pregnant women. The results showed that AUC(HBA2)<AUC(MCHC)<AUC(RDW-SD)<AUC(MCH)<AUC(MCV) (P<0.01).@*CONCLUSION@#The most common genotypes of α- and β-thalassemia in pregnant women in Xindu District of Chengdu were --SEA /αα, CD41-42/N, CD17/N. The blood routine indicators (HBA2、RDW-SD、MCHC、MCH、MCV) have high diagnostic value for screening of thalassemia.

Study on Thalassemia in Han Population in Sanya of Hainan Province / 中国实验血液学杂志

OBJECTIVE@#To study the distribution characteristics of thalassemia genotype in Han Population in Sanya of Hainan Province.@*METHODS@#Gap PCR and reverse dot hybridization were used to detect and analyze the thalassemia gene in 572 suspected thalassemia carriers of Han Population in Sanya.@*RESULTS@#Among the 572 Han Population in Sanya, 271 cases of thalassemia gene abnormality were detected, among which 161 cases were founded to be carriers of α-thalassemia gene. A total of 9 genotypes were detected, in the following order of the detection rate was －－SEA/αα，－α3.7/αα，－α4.2/αα，－－SEA/－α3.7，－－SEA/－α4.2，－α4.2/－α4.2，－α3.7/－α4.2，－α3.7/－α3.7，－－SEA/－－SEA. Among them, the deletion type (－－SEA/αα) in southeast Asia was the most common, accounting for 66 cases. 99 cases of β-thalassemia were detected, there were 7 genotypes, all of which were heterozygous. The order of the detection rate was CD41-42/βN, IVS-II-654/βN, CD17/βN, CD71-72/βN, -28/βN, －29/βN, CD27-28/βN. Among them, CD41-42/βN was the most common, accounting for 51 cases. In addition, 11 cases of combined α and β thalassemia were detected. Five kinds of genotypes were checked out, the order of detection rate was －α3.7/αα composite CD41-42/βN, －－SEA/αα composite IVS-II-654/βN, －α4.2/－α4.2 composite CD41-42/βN, －α4.2/αα composite －29/βN , －－SEA/ －α4.2 composite CD41-42/βN.@*CONCLUSION@#Han Population in Sanya of Hainan Province is a high-risk population of thalassemia, the genotype characteristics are different from other areas with high incidence of thalassemia in China. The main type of α-thalassemia is the deficiency mutation of southeast Asia, while CD41-42 heterozygous mutation is the main type of β-thalassemia.

Genetic Analysis and Prenatal Diagnosis of Thalassemia in Couples of Childbearing Age in Quanzhou Region Fujian Province, China / 中国实验血液学杂志

OBJECTIVE@#To explore the genotypes and prenatal diagnosis of thalassemia in couples of childbearing age in Quanzhou, Fujian Province.@*METHODS@#Blood routine and hemoglobin electrophoresis were performed for initial thalassemia screening in 76 328 couples in Quanzhou region from July 2017 to July 2020. The couples with positive initial screening results further underwent thalassemia gene test. Couples carrying homotypic thalassemia genes underwent prenatal diagnosis in the second trimester.@*RESULTS@#Among 76 328 couples of childbearing age, 1 809 couples of positive initial thalassemia screening were identified, with the positive rate about 2.37%. Further results of genetic detection of the 1 809 couples showed that 985 cases were diagnosed as α- thalassemia, of which --sea/αα was the most frequency, followed by -α3.7/αα and ααQS/αα; 296 cases were diagnosed as β-thalassemia, the most frequency mutations were 654M/N and 41-42M/N; 26 cases of compound α and β-thalassemia were detected. In addition, 3 rare cases of thalassemia were detected, including --THAI/αα, SEA-HPFH, and -α6.9/--sea. Among them, 108 couples were confirmed as homologous thalassemia, with the detection rate about 5.97%, including 96 couples of homologous α-thalassemia, 9 couples of homologous β-thalassemia, and 3 couples with one had compound α- and β-thalassemia. Among them, 17 couples with homologous α-thalassemia underwent prenatal diagnosis in the second trimester, of which 1 case of Hb Bart's Hydrops Syndrome, 3 cases of HbH disease, 9 cases of silent thalassemia or α-thalassemia minor, and 4 cases of healthy fetuses were detected. Fetal chromosome karyotype analysis showed that 16 cases were normal and 1 case diagnosed as Down syndrome.@*CONCLUSION@#Thalassemia screening in pre-marital and pre-pregnancy, and prenatal diagnosis can effectively reduce the birth of children with thalassemia intermediate and thalassemia major. It is necessary to perform chromosome karyotype analysis at the same time as prenatal diagnosis of thalassemia gene in order to avoid fetus with abnormal chromosome.

Hematological Characteristics of Different Genotypes of Thalassemia among Reproductive Population in Chongqing / 中国实验血液学杂志

OBJECTIVE@#To investigate the hematological characteristics and genotype distribution of thalassemia among people at reproductive age in Chongqing.@*METHODS@#Hematology analysis and capillary electrophoresis were performed in 29 145 participants at reproductive age. The patients with positive results were confirmed by thalassemia genotyping. Genotype distribution and characteristics of mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and hba2 levels in thalassemia patients were analyzed.@*RESULTS@#--SEA/αα (45.10%), -α3.7/αα (39.31%) and -α4.2/αα (8.46%) were the most common genotypes of α-thalassemia, while CD17 (HBB: c. 52A>T) (31.67%), CD41-42 (HBB: c. 126-129 del TTCT) (26.87%) and IVS-Ⅱ-654 (HBB: c. 316-197 C>T) (24.21%) were the most common genotypes of β-thalassemia in Chongqing. In α-thalassemia ααCS/αα showed the lowest hba2 value (2.18±0.23)%, while --SEA/αα showed the lowest MCV (71.9±8.5) fl and MCH (22.7±3.3) pg value. The patients in βE (HBB: c. 79G>A) group showed comparatively higher values of MCV and MCH and significantly lower HbA and hba2 values than the other genotypes. There was no significant difference in HbA, hba2, MCV, MCH levels of the patients between pregnant group and non-pregnant group.@*CONCLUSIONS@#In Chongqing, there are differences in hematological characteristics among patients with different thalassemia genotypes. There is no significant effect of pregnancy on HbA, hba2, MCV and MCH has been found.

Genetic Analysis of Thalassemia in 22 940 Pregnant Women in Xiangxi Tujia and Miao Autonomous Prefecture / 中国实验血液学杂志

OBJECTIVE@#To investigate the incidence and types of thalassemia in Xiangxi Tujia and Miao Autonomous Prefecture.@*METHODS@#Automatic capillary electrophoresis was used to screen the thalassemia phenotypes of 22 940 blood samples of pregnant women and puerperants collected in our hospital and some other medical institutions in the prefecture during 2017-2019, among which there were 3 356 cases of Tujia ethnicity, 2 821 cases of Miao ethnicity, and 2 233 cases of Han ethnicity included, whose ethnicity were indicated. The samples with positive result would undergo further genetic testing.@*RESULTS@#There were 2 314 cases of suspicious thalassemia were screened from 22 940 cases by the electrophoresis, thus the positive rate was 10.1% (hematological phenotypes from some other institutions were not included). Specifically, there were 1 706 cases with HBA2 less than 2.5%, 255 cases with HBA2 ranged from 2.5% to 3.5%, which displayed abnormal hematology (MCV or/and MCH) or other abnormal bands, and 353 cases with HBA2>3.5%. There were 436 suspected positive patients in 2 314 suspicious samples received further thalassemia gene testing in our hospital, among them 48 cases were diagnosed with α-thalassemia, 85 cases with β-thalassemia, and 2 cases as compound type. The positive diagnosis rate of α-thalassemia gene test was 11.0%, β-thalassemia was 19.4%, and positive pregnant women was 31.0%.@*CONCLUSION@#The positive rate of thalassemia screening in Xiangxi Autonomous Prefecture is roughly the same as that in other regions of Hunan. The positive predictive value of β-thalassemia screening is as high as 86%. Compared with the missed screening data, it is recommended to use hematology (MCV, MCH) method combined with capillary hemoglobin electrophoresis for thalassemia screening.

The value of combined detection of HbA2 and HbF for the screening of thalassemia among individuals of childbearing ages / 中华医学遗传学杂志

OBJECTIVE@#To assess the application value of combined detection of HbA2 and HbF for the screening of thalassemia among a population of childbearing age in Quanzhou, Fujian, and determine the optimal cut-off values for the region.@*METHODS@#Capillary hemoglobin electrophoresis and genetic testing for α and β globin gene mutations were simultaneously carried out on 11 428 patients with suspected thalassemia. Statistical methods were used to analyze the distribution of various types of thalassemia and compare the performance of HbA2 and HbF measurement for the screening of various types of thalassemia. The optimal cut-off values for HbA2 and HbF were determined with the ROC curves.@*RESULTS@#4591 patients with α, β, and αβ compound thalassemia were identified by genetic testing. The most common genotypes for α and β thalassemia included --SEA/αα and β654/βN, β41-42/βN, and β17/βN. The ROC curves were drawn to compare the performance of HbA2 screening for α-, β-, αβ-compound, static α-, mild α-, and intermediate α-thalassemia, and the maximum area under the curves was 0.674, 0.984, 0.936, 0.499, 0.731, 0.956, and the optimal cut-off values for HbA2 were 2.45%, 3.25%, 3.65%, 2.95%, 2.55%, 1.75%, respectively.@*CONCLUSION@#HbA2 is an efficient indicator for identifying intermediate types of α-, β-, and αβ compound thalassemia. The combination of HbA2 and HbF measurement can effectively detect carriers for β-thalassemia mutations.

Hematologic Phenotype and Genotype Analysis of Patients with Hemoglobin Variants / 中国实验血液学杂志

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.

Preimplantation Genetic Diagnosis of α/β Complex Thalassemia by Next Generation Sequencing / 中国实验血液学杂志

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.

Genetic Testing for Alpha and Beta Thalassemia in Children in Quanzhou Region of Fujian Province in China / 中国实验血液学杂志

OBJECTIVE@#To analyze the genotypes and distribution of thalassemia in children in Quanzhou Region so as to provide reference for the prevention and control of thalassemia.@*METHODS@#A total of 1 302 children with suspected thalassemia were collected from January 2014 to April 2020 in Quanzhou Region. The deletional α-thalassemia was detected by Gap-PCR, and DNA reverse dot blot (RDB) hybridization was used to detect α- and β-thalassemia mutations.@*RESULTS@#In the 1 302 cases, 667 cases were identified as thalassemia carriers, and the positive detection rate was about 51.23%. Among them, 380 cases of α-thalassemia gene were detected, and --@*CONCLUSION@#There are various genotypes of thalassemia in children in Quanzhou Region, and many children with thalassemia major or intermedia. Therefore, further prevention and control of thalassemia need to be strengthened for reducing the birth of thalassemia major or intermedia.

Retrospective Analysis of Hematological Phenotypes in Patients with Gene Mutation and Deletion α-Thalassemia / 中国实验血液学杂志

OBJECTIVE@#To explore the differences between hematological phenotypes of patients with different genotypes in gene mutations and deletion α- thalassemia.@*METHODS@#By screening the α- thalassemia gene test results in the First Affiliated Hospital, Sun Yat-Sen University from January 2015 to April 2020, the patients with mutation and deletion α- thalassemia were obtained, then the differences between hematological phenotypes of patients with different genotypes were analyzed.@*RESULTS@#There were 96 patients with mutation combined with deletion α- thalassemia from the results of 24 054 α- thalassemia patients screened out, including 79 patients with non-deletion Hb H disease (α@*CONCLUSION@#The hematological phenotype changes caused by α

Genotypes of thalassemia in children: an analysis of 30 417 cases / 中国当代儿科杂志

OBJECTIVES@#To investigate the distribution of genotypes of thalassemia in children in Guangxi, China.@*METHODS@#A total of 30 417 children with positive results of thalassemia screening in the Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region from January 2011 to December 2019 were enrolled. Single-tube multiplex PCR, agarose gel electrophoresis, and reverse dot blot hybridization technique were used for the detection of common α- and β-thalassemia genes. Gap-PCR or gene sequence analysis was performed for 2 703 children suspected of rare thalassemia.@*RESULTS@#Among the 30 417 children with positive results of thalassemia screening, 23 214 (76.32%) were diagnosed with thalassemia, and the detection rates of α-thalassemia, β-thalassemia, and α-thalassemia with β-thalassemia were 47.77%, 23.75%, and 4.80% respectively. A total of 13 types of α-thalassemia alleles (18 480 alleles in total) were detected, mainly --@*CONCLUSIONS@#There are diverse gene mutations and rich genotypes of thalassemia among children in Guangxi, and α-thalassemia is more common, with --

Application of DNA Microarray in Genetic Mutation Detection in Patients with Thalassemia / 中国实验血液学杂志

OBJECTIVE@#To perform dried blood spots thalassemia gene detection in patients with positive blood phenotypes by microarray technology, and evaluate its value in clinical detection.@*METHODS@#DNA samples were extracted from dried blood spots of 410 patients. Microarray technology was used to detect 3 deletion and 3 non-deletion types of α-thalassemia and 19 β-thalassemia point mutations which were common gene mutions in China.@*RESULTS@#There were 357 positive cases in all the 410 tested samples with the positive rate 87.07%, among which 299 cases (72.93%) carried deletion or point mutations of α-thalassemia, 29 cases (7.07%) carried point mutations of β-thalassemia and 29 cases (7.07%) carried gene mutations of complex αβ-thalassemia syndrome. The mutations of α-thalassemia were involved with --@*CONCLUSION@#The most common genetic mutations are --

Gene Detection Analysis of Thalassemia in 2 494 Cases of Childbearing Couples in Haikou City / 中国实验血液学杂志

OBJECTIVE@#To observe the genotypes and composition ratio of thalassemia in couples of reproductive age, and provide a reference for the prevention and control of thalassemia in Haikou.@*METHODS@#Gene diagnosis was performed in 2 494 subjects who were screened for thalassemia before marriage or prenatal by cross-breakpoint PCR, PCR-reverse dot hybridization, and PCR-electrophoresis.@*RESULTS@#A total of 1 037 thalassemia gene carriers were detected in 2 494 samples, with a detection rate of 41.57%, of which 75.02% was α-thalassemia, 18.61% was β-thalassemia, and 6.36% was α-β complex thalassemia. There were 778 cases of α-thalassemia, mainly of deletion type, accounting for 76.99% (599/778). Twenty genotypes were detected, the highest three was --@*CONCLUSION@#In Haikou city, the gene carrying rate of thalassemia is very high, and the genotype distribution is different from other cities in Hainan Province, attention should be paid to the impact of population inflow on the frequency spectrum change of local thalassemia gene.

Methodological Evaluation of Microarray in the Detection of α-Thalassemia / 中国实验血液学杂志

OBJECTIVE@#To proceed the clinical evaluation of DNA microarray for thalassemia gene detection.@*METHODS@#Peripheral blood samples of 166 thalassemia gene test subjects were collected and tested for thalassemia genes by microarray chip method and Gap-PCR method combined with PCR-reverse dot blot hybridization method according to double-blind control test. The specificity, sensitivity, positive predictive value, negative predictive value, and total coincidence rate of the microarray chip method were evaluated. When the two methods were inconsistent, multiplex ligation dependent probe amplification (MLPA) was used to verify the deletional α-thalassemia.@*RESULTS@#Compared with Gap-PCR method, specificity, sensitivity, positive predictive value, negative predictive value, Youden index, and total coincidence rate of microarray chip method was 100% (70/70), 96.88% (93/96), 100% (93/93), 95.89% (70/73), 0.969, and 97.59% (162/166), respectively, while compared with PCR-reverse dot blot hybridization method was 100% (125/125), 100% (41/41), 100% (41/41), 100% (125/125), 1, and 100% (166/166), respectively.@*CONCLUSION@#The microarray chip method for α-thalassemia gene detection shows the advantages of high specificity, sensitivity, and throughput.

Hb Bart's Quantitative Analysis in the Screening of α-Thalassemia / 中国实验血液学杂志

OBJECTIVE@#To research the relationship between difference types of α-thalassemia gene types and Hb Bart's hemoglobin bands.@*METHODS@#Capillary electrophoresis was used to screen thalassemia gene for the newborn form January 2020 to December 2020, and the thalassemia gene was detected by PCR or PCR-NGS in the positive patients. The relationship between α-thalassemia gene and Hb Bart's hemoglobin was compared and analyzed statistically.@*RESULTS@#There were significant differences in Hb Bart's hemoglobin among the different α-thalassemia mutation types, Hb Bart's was the highest in --SEA/-α@*CONCLUSION@#The Hb Bart's content of different genotypes of α-thalassemia are significantly different. The Hb Bart's content shows high application value in α-thalassemia screening and genotyping identification.