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 investigate characteristics of silent alpha thalassemia genes in child-bearing adults in Guangdong, in order to provide data for the prevention and control of hemoglobin H disease. METHODS: A total of 8 752 cases were collected from January 2016 to December 2020. Gap-PCR was used to detect the deletional of α-thalassemia mutations (-α^3.7, -α^4.2), while PCR reverse dot blot hybridization assay (RDB) was used to detect the non-deletional α-thalassemia mutations (Hb CS, Hb QS and Hb Westmead). RESULTS: Among 8 752 subjects, 717 cases of silent α-thalassemia were detected, the detection rate was 8.19%, including 555 cases of deletional α-thalassemia (77.41%) and 162 cases of non-deletional α-thalassemia 22.59%. The mean corpuscular volume (MCV) of deletional silent α-thalassemia was (82.09±4.10) fl, and mean corpuscular hemoglobin (MCH) was (27.03±1.37) pg, which both were over the diagnostic cut-off value for thalassemia. The MCV of non-deletional silent α-thalassemia was (81.07±4.93) fl, and MCH was (26.77±2.20) pg. According to the diagnostic criteria, if using MCV<82 fl or (and) MCH<27 pg as a positive criteria for screening thalassemia in the childbearing age, the screening sensitivity was 53.14% and different in different genotype, among which αα^QS/αα was 100%, -α^3.7/αα, -α^4.2/αα, αα^CS/αα and αα^WS/αα was 62.15%, 63.41%, 44.83% and 39.62%, respectively. Namely, nearly half the carriers of such mutations might have escaped detection as a result of their screening strategy. CONCLUSION When a couple is preparing for pregnancy, if one of them has been determined to be mild α-thalassemia or hemoglobin H disease, other half is necessary to carry out silent α thalassemia detection to prevent the birth of children with hemoglobin H disease even if MCV>82 fl and MCH>27 pg.
Adult ; Pregnancy ; Female ; Humans ; alpha-Thalassemia/diagnosis* ; Genotype ; Mutation ; Erythrocyte Indices ; Polymerase Chain Reaction ; China ; beta-Thalassemia/genetics*

OBJECTIVE: To compare the performance of high-throughput sequencing technology in prenatal thalassemia screening in Zhuhai area through comparison with traditional methods. METHODS: A total of 1463 pregnant women were randomly selected. Following DNA extraction, high-throughput sequencing and conventional three-step thalassemia screening were carried out for each sample. Inconsistent results samples were validated by quantitative fluorescence PCR (QF-PCR) or Sanger sequencing. The results by the two methods were compared. RESULTS: Among the 1463 cases, 318 (21.74%) were detected by conventional method, which included 210 (14.35%) with α-thalassemia, 97 (6.63%) with β-thalassemia, 11 (0.75%) with composite α- and β-thalassemia. Meanwhile, 379 cases (25.91%) of thalassemia were detected by high-throughput sequencing, which included 260 (17.77%) with α-thalassemia, 107 (7.31%) with β-thalassemia, 12 (0.82%) with composite α- and β-thalassemia. Six one cases were missed by the conventional method, which yielded a missed diagnosis rate of 16.09%, including 50 cases of α- thalassemia,10 cases of β-thalassemia, and 1 case of α-compound β-thalassemia. No cases of thalassemia were missed by high-throughput sequencing, and 10 rare thalassemia genotypes were detected. CONCLUSION High-throughput sequencing technology can improve the detection rate of thalassemia and reduce the missed diagnosis rate. It has a high application value in prenatal thalassemia screening in Zhuhai area and can more effectively prevent the birth of patients with severe thalassemia.
China ; Female ; Genotype ; High-Throughput Nucleotide Sequencing ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis/methods* ; Technology ; alpha-Thalassemia/genetics* ; beta-Thalassemia/genetics*

OBJECTIVE: To investigate the molecular epidemiological characteristics of common δβ-thalassemia/hereditary persistence of fetal hemoglobin(HPFH) in the prepregnant population in Huadu, and to provide a laboratory basis for prevention and control of thalassemia. METHODS: Blood samples of childbearing age people in Huadu District of Guangzhou who participated in free thalassemia testing from January 2016 to July 2021 were collected for hematological parameters analysis and hemoglobin electrophoresis. Chinese ^Gγ⁺(^Aγδβ)⁰-thalassemia, ^SEA-HPFH and Taiwanese deletion β-thalassemia were detected by Gap-PCR in the samples with higher HbF(≥5%). Primers were designed for the proximal HBG1 and HBG2 promoter, and the point mutations in the proximal promoter region were detected by Sanger sequencing. Hematology parameters data were statistically analyzed. RESULTS: Among 27 088 samples, Thirteen cases of Chinese ^Gγ⁺(^Aγδβ)⁰-thalassemia and thirty-three cases of ^SEA-HPFH were detected, which including 3 cases of Chinese ^Gγ⁺(^Aγδβ)⁰/β^N compounded with --^SEA/αα and three cases of ^SEA-HPFH/β^N compounded with --^SEA/αα. 6 carriers with ^Aγ-196 C>T were also detected; No Taiwanese thalassemia genetype was detected. The total detection rate of common δβ-thalassemia/HPFH was 0.19% (52/27 088). There were significant differences in the levels of MCV, MCH, HbA₂, and HbF among Chinese ^Gγ⁺(^Aγδβ)⁰-thalassemia, ^SEA-HPFH, ^Aγ-196 C>T (P<0.001). The hematological parameters of ^Aγ-196C>T combined with α⁰-thalassemia were similar to those of Chinese ^Gγ⁺(^Aγδβ)⁰-thalassemia carriers, and only HbA₂ was significantly lower than that of the latter, which was helpful for clinical identification. CONCLUSION δβ-thalassemia/HPFH should be included in the scope of thalassemia prevention program in the prepregnant population in Huadu District, and hematological parameters can provide some basis for identifying different types of δβ-thalassemia/HPFH.
Diagnosis, Differential ; Fetal Hemoglobin/genetics* ; Heterozygote ; Humans ; Thalassemia/genetics* ; beta-Thalassemia/genetics*

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 -α^3.7/αα and αα^QS/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 -α^6.9/--^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.
Child ; China ; Female ; Genetic Testing ; Genotype ; Humans ; Pregnancy ; Prenatal Diagnosis ; alpha-Thalassemia/genetics* ; beta-Thalassemia/genetics*

OBJECTIVE: To identify one case of rare Hb Lepore-BW associated with IVS-II-654 heterozygous mutation in Sichuan area. METHODS: The blood routine examination and hemoglobin electrophoresis methods were used to analyze the blood routine parameters, HbA₂ and HbF in the samples of peripheral blood in proband and his parents, as well as the cord blood of pregnant woman. The detection of thalassemia gene and Sanger sequencing methods were used to detect the hemoglobin mutations. RESULTS: The result showed that the Hb Lepore-BW heterozygous mutation was detected in the father of the proband, while a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation was detected in the proband, as well as his mother and cord blood were both detected as IVS-II-654 heterozygous mutation. CONCLUSION The study identified a rare Hb Lepore-BW with IVS-II-654 heterozygous mutation, which was characterized by intermediate β-thalassemia. It is necessary to hemoglobin electrophoresis combined with routine blood testing in prenatal screening.
Female ; Hemoglobins, Abnormal/genetics* ; Heterozygote ; Humans ; Infant, Newborn ; Male ; Mutation ; Pregnancy ; Prenatal Diagnosis ; beta-Thalassemia/genetics*

OBJECTIVE: To understand the genotypes and distribution characteristics of thalassemia in Baise, Guangxi Zhuang Autonomous Region, to provide references for the prevention and diagnosis of thalassemia in the region and improve the quality of eugenics. METHODS: 3 482 pregnant women and their spouses from January 2019 to August 2019 in Baise Maternal and Child Health Hospital for prenatal genetic diagnosis were selected, α, β- thalassemia genes were detected by Gap-PCR, PCR and DNA reverse dot hybridization, cases carrying thalassemia gene were confirmed and statistical analyzed. RESULTS: 2 260 samples (64.90%) carrying thalassemia gene were found, among which 1 459 cases (64.56%) were diagnosed as α- thalassemia, 617 cases (27.30%) as β- thalassemia, 184 cases (8.14%) as α complex β- thalassemia. Among 1 459 α- thalassemia genes, --SEA /αα(637 cases, 43.66%), -α3.7 /αα (306 cases, 20.97%), -αCS /αα(143 cases, 9.80%), -α4.2 /αα(124 cases, 8.50%) and -αWS /αα(77 cases, 5.27%) were the most common, while among 617 β- thalassemia genes, CD17 (229 cases, 37.12%), CD41-42 (213 cases, 34.52%), IVS-I-1 (41 cases, 6.65%), βE (38 cases, 6.16%) and CD71-72 (34 cases, 5.51%) were the most common. And --SEA /αα/ CD17 (24 cases, 13.04%), -α4.2 /αα/ CD17 (13 cases, 7.07%), -α3.7 /αα/ CD41-42 (12 cases, 6.52% ) and --SEA /αα/ CD41-42 (12 cases, 6.52%) were mainly found in 184 cases of α complex β - thalassemia. CONCLUSION Genotyes of thalassemia in Baise, Guangxi Zhuang Autonomous Region are complex and diverse. The prenatal screening and diagnosis of thalassemia in the region should be strengthened in accordance with the characteristics of genetypes in the region, in order to reduce birth defects and improve eugenics quality.
Child ; China ; Female ; Genotype ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis ; alpha-Thalassemia/genetics* ; beta-Thalassemia/genetics*

OBJECTIVE: To analyze the hematological characteristics of Chinese METHODS: Hemoglobin electrophoresis and blood routine test were used to analyze the hematological indexes of all peripheral blood samples，PCR-Flow fluorescent hybridization and Gap-PCR were used to detect the globin gene mutations and the data were analyzed statistically. RESULTS: The 3 types of deletion β- Thalassemia patients were showed as hypochromic small cell anemia. The MCH and MCV values of Taiwan type β-thalassemia patients were the lowest. The results of hemoglobin electrophoresis showed that the increasing of HbF was found in all of the 3 types. Except for the decreasing of Hb A2 in Chinese CONCLUSION Through analyze the hematological characteristics, it can be provide that the guidance for the differential diagnosis and genetic consultation of the three commonest deletion β-thalassemia in Chinese.
China ; Diagnosis, Differential ; Fetal Hemoglobin ; Humans ; Mutation ; Thalassemia ; 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 investigate the relationship between umbilical cord blood erythrocyte index and thalasse-mia, and reveal its clinical value in the screening of thalassemia in neonates. METHODS: 2 919 cases of umbilical cord blood from neonatal who were born in Boai Hospital of Zhongshan Affiliated with Southern Medical University from July 2017 to December 2018 were collected, the routine blood tests were preformed to detect the umbilical cord blood. Thalassemia gene in peripheral blood of neonates was collected. The cut-off values of cord blood indexes were determined, and the sensitivity, specificity and other evaluation indexs were calculated. RESULTS: Among the cord blood in 2 919 neonates, 314 cases were detected out as thalassemia(positive rate: 10.76%). The average level of RBC and RDW in 2 605 children with non-thalassemia was lower than those with 314 children with thalassemia. The levels of Hb, MCV, MCH, MCHC, HCT, Hb/RBC and MCV/RBC in children with non-thalassemia were higher than those with thalassemia, and there were significant differences in the neonates between the two groups. The RBC and RDW levels of neonates in the α-thalassemia group were higher than those in the non-thalassemia group, while the levels of Hb, MCV, MCH, MCHC, HCT, Hb/RBC and MCV/RBC of neonates were lower than those in the non-thalassemia group. The levels of MCV, MCH and Hb/RBC of neonates in the β-thalassaemia group were lower than those in the non-thalassaemia group. The levels of MCV, MCH, Hb/RBC, and MCV/RBC of neonates in the complex thalassemia group were lower than those in the non-thalassemia group. When the cut-off value of MCV was set to 106.05 fl, the sensitivity was 0.548, and the specificity was 0.907, the specificity was the highest among all indexes. The area under the ROC curve of the combined diagnosis of MCH+MCV/RBC was the largest(0.807), the sensitivity was 0.710, the specificity was 0.841, the positive predictive value was 0.348, and the negative predictive value was 0.960. CONCLUSION The single indicator of umbilical cord blood red blood cells has advantages and disadvantages for the screening of thalassemia, but the combination of MCH+MCV/RBC can improve the accuracy of the screening or diagnosis of thalassemia, it also has a positive effect to the reduction of the birth rate of children with thalassemia major, which showed a high popularization value in primary hospitals.
Child ; Erythrocyte Indices ; Fetal Blood ; Humans ; Infant, Newborn ; Mass Screening ; alpha-Thalassemia/diagnosis* ; beta-Thalassemia