OBJECTIVE: To identify the gene mutation types of 4 suspected β-thalassemia patients in Yunnan Province, and to analyze the genotypes and hematological phenotypes. METHODS: Whole genome sequencing was performed on the samples of 4 suspected β-thalassemia patients from the Dai ethnic group in a thalassemia endemic area of Yunnan Province, whose hematological phenotypes were not consistent with the results of common thalassemia gene mutations. The mutations of β-globin gene clusters were confirmed by polymerase chain reaction (PCR) and Sanger DNA sequencing technology. RESULTS: The 3.5 kb deletion in β-globin gene cluster (NC_000011.10: g. 5224302-5227791del3490bp) was detected in 4 patients' samples, of which 1 case was also detected with HbE mutation and 1 case with CD17 mutation. These 2 patients displayed moderate anemia phenotype, while the two patients with only the 3.5 kb deletion presented with other mild anemia phenotype. CONCLUSION Heterozygous carriers with rare 3.5 kb deletion of the β-globin gene cluster may develop mild anemia, compound mutations of the 3.5 kb deletion with other mutations may led to intermediate thalasemia with moderate to sever anemia. In areas with a high incidence of thalassemia, suspected patients should undergo genetic testing to avoid missing or misdiagnosing rare mutations.
Humans ; beta-Globins/genetics* ; Multigene Family ; beta-Thalassemia/genetics* ; Mutation ; Genotype ; Sequence Deletion ; Phenotype ; Male ; Female

OBJECTIVE: To analyze the incidence of abnormal hemoglobin (Hb) in neonates in Guangzhou area, as well as the results of quantitative analysis of Hb in neonatal umbilical cord blood and genetic diagnosis of thalassemia in neonates with abnormal Hb; And to explore the hematological phenotypes and clinical characteristics of neonates with abnormal Hb and their parents, providing a reference for eugenics and childcare. METHODS: 650 neonates born at Guangdong Provincial People's Hospital who underwent Hb electrophoresis were included in this study. The results of routine blood test of umbilical cord blood , Hb electrophoresis and α-, β-thalassemia gene detection of the neonates were collected. The genotype distribution of thalassemia in the neonates was analyzed. Additionally, the abnormal Hb content of α and β variants was studied. Furthermore, the differences in hematological parameters between abnormal Hb neonates and normal neonates and α-thalassemia neonates, as well as between the parents of abnormal Hb neonates and normal adults were compared. RESULTS: Among the 650 neonates, 332 (51.08%) were diagnosed with thalassemia, including 235 cases of α-thalassemia (36.15%), 79 cases of β-thalassemia (12.15%), and 18 cases of compound αβ-thalassemia (2.77%). Among all the α-thalassemia genotypes, the most prevalent one was -- ^SEA/αα (48.94%), followed by -α^3.7/αα (20.00%), -α^4.2/αα (11.06%), and αα^CS/αα (8.94%). The four most common genotypes of β-thalassemia were β^CD41-42 (32.91%), β^IVS-Ⅱ-654 (26.58%), β^-28 (21.52%), and β^E (10.13%), respectively. 275 cases of abnormal bands were found in Hb electrophoresis of umbilical cord blood, with a detection rate of 42.31%. The abnormal Hb content of α-variant in the neonates was significantly higher than that of β-variant (P < 0.001). The levels of Hb, MCV, MCH, Hb A, and Hb F in neonates with abnormal Hb were lower than those in normal neonates, while the RDW-CV was higher than that in normal neonates, with statistical significantce (P < 0.05). The levels of RBC and Hb A in neonates with abnormal Hb were lower than those in neonates with α-thalassemia, while the level of MCH was higher than that in neonats with α-thalassemia, with statistical significance (P < 0.05). The levels of Hb, MCV, MCH, and Hb A in parents of neonates with abnormal Hb were lower than those in normal adults, while the RDW-CV was higher than that in normal adults, and the differences were statistically significant (P < 0.05). CONCLUSION The abnormal Hb content of α-variant in the neonates is significantly higher than that of β-variant in the neonates in Guangzhou, which can help to presume whether it is α chain or β chain based on the abnormal Hb content, providing a reference for globin gene sequencing. Meanwhile, analysis of various hematological screening-related indicators in neonates in the early stage is beneficial for early warning of the occurrence of abnormal Hb combined with thalassemia, reducing missed diagnoses to a certain extent.
Humans ; Infant, Newborn ; Genotype ; Hemoglobins, Abnormal/genetics* ; China/epidemiology* ; alpha-Thalassemia/epidemiology* ; beta-Thalassemia/genetics* ; Parents ; Female ; Male ; Fetal Blood

OBJECTIVE: To investigate the gene carrier rate and genotype distribution characteristics of thalassemia in the population of Kunming, and compare the differences of red blood cell (RBC) parameters between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy population, as well as between different sexes of adults aged 18-45 years. METHODS: A retrospective analysis of 3 195 cases of thalassemia gene screened in the First Affiliated Hospital of Kunming Medical University from April 1, 2020 to March 31, 2022 was performed to detect 21 mutations of β-globin genes which was common in Chinese people using fluorescence PCR melting curve method. Patients with single heterozygous carrying β-thalassemia gene were divided into β⁺ heterozygote group and β⁰ heterozygote group, while the control group consisted of 219 healthy individuals. Four indices, including RBC, hemoglobin (Hb), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were collected from all β heterozygous carriers and 219 healthy people, and compared between β⁺ heterozygote group, β⁰ heterozygote group and control group, as well as between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy population of different sexes aged 18-45 years. RESULTS: There were 688 cases confirmed thalassemia gene carriers, accounting for 21.53%. Among them, 322 cases were found to have β-globin gene mutations, including 145 cases of β⁺ heterozygote, 151 cases of β⁰ heterozygote, and 14 cases of β⁺ homozygotes as well as β⁺ and β⁰ dual heterozygotes. Additionally, 12 cases were found to have simultaneous mutation or deletion of β-globin and α-globin. The carrier rate of CD26 G>A mutation in β⁺ thalassemia was the highest, accounting for 57.9%, while in β⁰ thalassemia CD17 A>T was the highest, accounting for 46.4%. The erythrocyte parameters of 296 β heterozygous mutation carriers were compared with the normal reference interval, and it was found that 218 cases with RBC value greater than the highest value of reference interval, while 105, 281, and 269 cases with Hb, MCV, and MCH value less than the lowest value of reference interval, respectively. There were significant differences in the 4 erythrocyte parameters between β⁺ heterozygotes, β⁰ heterozygotes and healthy individuals (all P < 0.001), and further comparison between different sexes also showed significant differences (all P < 0.001). CONCLUSIONS The carrier rates of thalassemia gene and β-thalassemia heterozygote are both at high level in Kunming, and there are significant differences in the erythrocyte parameters between β⁺ heterozygous carriers, β⁰ heterozygous carriers and healthy individuals. When genetic counseling, it is necessary to inform and strengthen screening among adults of marriageable age to prevent birth of children with severe thalassemia.
Humans ; beta-Thalassemia/blood* ; Adult ; Heterozygote ; Male ; Female ; beta-Globins/genetics* ; Retrospective Studies ; Middle Aged ; Mutation ; Adolescent ; Genotype ; Erythrocytes ; Erythrocyte Indices ; Young Adult ; China ; Genetic Testing ; Asian People/genetics*

OBJECTIVE: To investigate the common genotypes and distribution characteristics of thalassemia in Guiyang region, and preliminarily analyze the rare mutations of globin genes in this area. METHODS: A total of 9 334 individuals who came to our hospital for thalassemia screening from June 2016 to February 2023 were included in this study. They were examined for common thalassemia mutations using PCR-based flow-through hybridization technology. Meanwhile, rare and unknown mutations were detected by Sanger sequencing. RESULTS: Among the 9 334 cases, 895 positive cases of common thalassemia were detected, with a positive rate of 9.59%. Among the positive samples, 565 cases (63.13%) were confirmed to be α thalassemia, of which the most common genotypes were αα/-α^3.7 (46.37%), followed by αα/--^SEA(26.55%) and αα/-α^4.2(10.62%); 310 cases (34.64%) were diagnosed as β thalassemia, with β^CD17/β^N (39.35%) being the most frequent genotype, followed by β^CD41-42 /β^N (31.29%) and β ^IVS-II-654/ β^N (12.90%). There were 20 cases (2.23%) of αβ complex thalassemia, mainly being αα/-α^3.7 combined with β^CD17 /β^N . Additionally, 8 cases of rare globin gene mutations were found by Sanger sequencing, including 7 mutation types. Among them, HBB: c. -137C> T (-87 C>T) was reported for the first time in Guizhou; HBA1 : c.*29C>T and HBB : c. 93-50C>T (IVS I-81C>T) were new mutations that had not been recorded in either the HbVar or IthaGenes database. CONCLUSION Guiyang region has a high incidence of thalassemia mutations, and these mutations are diverse and complex. Analyzing gene mutation types of thalassemia in this area can contribute to the prevention of the birth of children with severe thalassemia.
Humans ; Genotype ; Mutation ; beta-Thalassemia/genetics* ; alpha-Thalassemia/genetics* ; Thalassemia/epidemiology* ; Genetic Testing ; China/epidemiology* ; Male ; Female

OBJECTIVE: To explore the expression and function of microRNA-144 (miR-144) in β-thalassemia (β-thal). METHODS: The expression of miR-144 during the differentiation of murine erythroleukemia (MEL) cells and mouse embryonic liver-derived erythroid precursor cells was analyzed by real-time fluorescence quantitative PCR (qRT-PCR); The expression levels of miR-144 in peripheral blood and day-14.5 embryonic hepatocytes of wild-type (WT) and β-thal mice, as well as the expression levels of miR-144 in peripheral blood of β-thal patients, was also measured by qRT-PCR. The proportion of Ter119 and CD71 double positive cells in peripheral blood of mild and severe β-thal mice was analyzed by flow cytometry, and the expression levels of miR-144 in the peripheral blood of mild and severe β-thal mice and patients were compared; Bone marrow nucleated erythrocytes from WT mice and β-thal mice were sorted and the expression levels of miR-144 potential target genes were analyzed by gene chip. RESULTS: The expression levels of miR-144 were gradually increased during the directed differentiation of mouse MEL cells and embryonic hepatocytes to the erythroid lineage (r _MEL=0.97, r _{embryonic hepatocytes}=0.86); Compared with WT mice, the expression levels of miR-144 in peripheral blood and 14.5-day embryonic hepatocytes of β-thal mice were significantly increased (P < 0.05); Compared with healthy controls, the patients with β-thal showed an increased expression levels of miR-144 in peripheral blood (P < 0.05). Compared with mice and humans with mild β-thal, the expression levels of miR-144 in peripheral blood of those with severe β-thal were significantly increased (P < 0.05). The expressions of potential target genes of miR-144 in nucleated erythroid cells of the β-thal mice were significantly reduced compared to the WT group. CONCLUSION The expression level of miR-144 gradually increases in erythroid development, and compared with mild β-thal patients, the expression level of miR-144 in the peripheral blood is higher in severe β-thal patients. MiR-144 is expected to be an auxiliary diagnostic indicator for β-thal in clinical practice.
MicroRNAs/metabolism* ; beta-Thalassemia/genetics* ; Animals ; Mice ; Humans ; Cell Differentiation ; Hepatocytes

OBJECTIVE: To retrospectively analyze the genetic differences of thalassemia gene mutations among ethnic groups in Hechi, Guangxi. METHODS: A total of 15 595 whole blood samples of residents of Hechi from January 1, 2020 to June 30, 2023 were screened for thalassemia, and the Gap-PCR method and RDB-PCR method were used to perform genetic testing on the positive samples. Gene sequencing was performed on the samples with positive screening results but negative genotyping results. RESULTS: Among the 15 595 samples, 10 501 cases were screened positively, and 8 506 cases were thalassemia gene carriers among the positive samples, with a positive coincidence rate of 81.00%. Among them, there were 5 374 cases of α-thalassemia, 2 531 cases of β-thalassemia, and 601 cases of α+β compound thalassemia. A total of 13 mutant types were detected in α-thalassemia, including --^SEA (48.57%), -α ^3.7 (31.31%), α ^CS (8.57%) and -α ^4.2 (8.07%). A total of 17 mutant types were detected in β-thalassemia, mainly CD17 (48.27%) and CD41-42 (41.24%). The thalassemia gene carriers were mainly from the Zhuang (6 106 cases), Han (969 cases), Yao (793 cases), Mulam (275 cases), and Maonan (228 cases) ethnic groups. The comparison of constituent ratios within the above five ethnic groups demonstrated that there were differences in the proportions of -- ^SEA, -α ^3.7, α ^CS , and -α ^4.2 among the Zhuang, Han, and Yao ethnic groups (P < 0.005). The proportion of α ^CS in the Mulam ethnic group was not significantly different from -α ^3.7 and -α ^4.2. The proportions of -- ^SEA, -α^3.7, and α ^CS in the Maonan ethnic group were not significantly different. There were no significant differences in the proportion of CD17 and CD41-42 among the Han, Yao, Mulam and Maonan ethnic groups. The proportion of --^SEA was the highest in the Mulam ethnic group (56.68%), which was statistically different from 35.92% in the Maonan ethnic group. The proportion of -α ^3.7 was the highest in the Zhuang ethnic group (33.25%), and the difference was statistically significant compared to the Mulam ethnic group which had the lowest proportion (18.72%). The proportion of α ^CS was the highest in the Maonan ethnic group (27.46%), and the differences were statistically significant compared with other ethnic groups. The proportions of CD17 in the Zhuang and Maonan ethnic groups (50.79%, 55.68%) were higher than those in the Han (39.12%), Yao (39.63%) and Mulam (30.00%), and the differences were statistically significant. There was no significant difference in the proportion of CD41-42 among the above five ethnic groups. CONCLUSIONS The mutation type and distribution differences of genes causing thalassemia among main ethnic groups in the minority inhabited areas of Hechi, Guangxi, show the characteristics of ethnic differentiation. The result is helpful to develop a special prevention and control plan for thalassemia in line with the population distribution characteristics, and provide reference for revealing the genetic background and geographical distribution of thalassemia in this area.
Humans ; China ; beta-Thalassemia/genetics* ; Ethnicity/genetics* ; alpha-Thalassemia/genetics* ; Mutation ; Genotype ; Retrospective Studies ; Asian People/genetics* ; Thalassemia/genetics* ; Male

OBJECTIVE: To analyze the distribution of thalassemia (referred to as "thalassemia") gene variant types in the population of the Wuhan area, aiming to provide a genetic basis for the precise prevention and control as well as clinical diagnosis of thalassemia in the Wuhan region. METHODS: In this study, 2 133 suspected thalassemia patients and individuals undergoing prenatal screening who visited the Department of Hematology, Obstetrics and Gynecology, Reproductive Medicine, Pediatrics, and Neurology at Wuhan First Hospital from October 2022 to October 2024 were selected as the research subjects. Peripheral blood samples were collected from the patients. The common 27 thalassemia genotypes of α- and β-thalassemia were initially screened using fluorescence PCR melting curve analysis technology. For samples where the fluorescence PCR melting curve results indicated unknown variants or where the clinical phenotype was inconsistent with the common genotypes, Sanger sequencing technology was used for review and verification. RESULTS: Among the 2 133 specimens analyzed, common thalassemia gene variants were detected in 210 cases (9.85%, 210/2 133). A total of 156 cases (8.05%, 156/1 938) of thalassemia gene variants were detected in females and 54 cases (27.69%, 54/195) in males. A total of 94 cases (4.41%, 94/2 133) of α-thalassemia were detected, including 46 cases (2.16%, 46/2 133) of silent α-thalassemia, 47 cases (2.20%, 47/2 133) of mild α-thalassemia, and 1 case (0.05%, 1/2 133) of intermediate α-thalassemia. Additionally, 111 cases of β-thalassemia were identified (5.20%, 111/2 133), including 51 cases of β/β⁺ thalassemia (2.39%, 51/2 133), 59 cases of β/β⁰ thalassemia (2.77%, 59/2 133), and 1 case of β⁺/HbE thalassemia (0.05%, 1/2 133). αβ-composite thalassemia gene variants were detected in 5 cases (0.23%, 5/2 133), including 1 complex variant with a genotype of --^SEA/αα combined with CD41-42 (-TTCT) and 29(A>G), representing a heterozygous variant of three genotypes. Rare globin gene variants were detected in 3 cases, including HBB:c.60C>T, HBB:c.-146G>T, and HBA2:c.*12G>A. CONCLUSION The Wuhan region exhibits a relatively high prevalence of thalassemia genes with notable gender disparities. While maintaining focus on thalassemia screening for females, enhanced males screening efforts and genetic counseling should be implemented in future prevention programs.
Humans ; Female ; Male ; Genotype ; beta-Thalassemia/genetics* ; China ; Thalassemia/genetics* ; alpha-Thalassemia/genetics* ; Genetic Variation

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.
Humans ; beta-Thalassemia/genetics* ; alpha-Thalassemia/genetics* ; Hemoglobinopathies/genetics* ; China/epidemiology* ; High-Throughput Nucleotide Sequencing

OBJECTIVE: To study the molecular epidemiology of thalassemia in Jiaxing area of Zhejiang province and provide a basis for prenatal diagnosis, genetic counseling and prevention and control of birth defects. METHODS: A total of 24 003 pregnant women who presented at the Jiaxing Maternal and Child Health Care Hospital from April 2017 to September 2021 were enrolled. Capillary hemoglobin electrophoresis in combination with routine blood test were used for primary screening for carriers of thalassemia-associated mutations, and those with positive results were subjected to fluorescence quantitative PCR assay. Prenatal diagnosis was provided for couples with a risk of giving birth to children with intermediate or severe thalassemia. RESULTS: Among the 24 003 pregnant women, 1 211 cases were suspected as carriers of thalassemia-associated mutations, among whom 443 (36.58%) were confirmed by genetic testing. Among these, carriers of α-, β- and α-complex β-globin gene mutations have accounted for 27.31% (121/443), 70.65% (313/443) and 2.04% (9/443), respectively. The result of prenatal diagnosis for an at-risk couple was --SEA/αCSα, and the fetus was predicted to have intermediate or severe thalassemia. Termination of the pregnancy was recommended. CONCLUSION Hemoglobin electrophoresis combined with routine blood test during pregnancy may be used as a preliminary screening measure for carriers of thalassemia-associated variants. Combined with genetic testing, this will be of great significance for the control of thalassemia in this region.
Female ; Humans ; Pregnancy ; Electrophoresis, Capillary ; Genetic Counseling ; Genetic Testing ; Mutation ; Prenatal Diagnosis ; Thalassemia/genetics*

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.
Humans ; alpha-Thalassemia/genetics* ; Retrospective Studies ; beta-Thalassemia/genetics* ; Genotype ; Phenotype ; Heterozygote ; China ; Mutation