Shine and Lal’s discrimination functions MCV2 x MCH x 0.01 was tested for its utility in diagnosing thalassemia trait. A2 and F determination on all samples with MCV2x MCHx0.01<1530. A value of more than 1530 rules out beta thalassemia trait. Ferritin quantitation were done on all samples to detect iron deficiency anemia. We have collected 103 samples with MCV2x MCHx0.01<1530. In this study, this method detected 91 cases as beta thalassemia trait (95%), 8 cases as HbE heterozygote, 1 case as iron deficiency anemia and 3 cases as normal.
Thalassemia ; diagnosis

50 samples of blood from patients diagnosed as betathalassemia in the center for blood transfussion and cryopreservation at minus 20oC and studied in the Mahidol University, where, DNA extracted by phenol and chloroform and the mutation analysed by technique of PCR and RDBH. The investigation of mutation that caused thalassemia help to establish the Center for the prenatal diagnosis, prevention and control of thalassemia in Vietnam.
beta-Thalassemia ; diagnosis ; mutation

Beta-Thalassemia is a blood disease with beta-globin deficiency caused by a directly down-regulation in the synthesis of structurally normal beta chains. Vent DNA polymerase is a high-fidelity thermophilic DNA polymerase, and the fidelity 5 - 15 times higher than Taq DNA polymerase (1/31,000 vs. 1/290 - 1/2,400). Using ARMS PCR (Amplification Refractor Mutation System-PCR) with Vent DNA polymerase, we found that 9/28 (32%) of the tested beta-Thalassemia patients had the mutation at codon 17 and 4/28 (14%) at codon 41/42. This method can be applied for a rapid prenatal diagnosis of beta-Thalassemia disease and has public health significance.
beta-Thalassemia ; DNA ; Polymerase Chain Reaction ; Diagnosis

Child ; Humans ; beta-Thalassemia ; diagnosis ; therapy

OBJECTIVETo describe a community-based model for prevention and control of severe alpha and beta thalassemias in Zhuhai city of Guangdong province.

METHODSCouples for premarital medical examination or regular healthcare examination in pregnancy were enrolled in this prospective screening program, which was supported by the two-level network composed of 6 local hospitals for testing thalassemias and follow-up for genetic counseling. A conventional heterozygote screening strategy was used to determine alpha and beta thalassemia traits in women and their partners according to the standard procedures of hematological phenotype analysis. Then confirmative diagnosis of alpha and beta thalassemia was performed on those couples suspected at-risk for severe thalassemia by using the PCR-based molecular diagnostic assays. The couples at-risk for severe thalassemia were counseled and offered prenatal diagnosis and termination of pregnancy in case of an affected fetus.

RESULTSDuring the period between January 1998 and December 2005, the screened records included 85522 young females and their partners for premarital screening and 10439 pregnant women for prenatal screening, with 71.38% coverage of total population recorded in this city for premarital screening. Six thousands five hundreds and sixty-three individuals in total were found to be the carriers of thalassemias, with 4312 for alpha thalassemia (4.5%) and 2251 for beta thalassemia (2.3%), respectively. One hundred and forty-eight couples were diagnosed to be at-risk for thalassemias, including 103 for alpha thalassemia and 45 for beta thalassemia, respectively. Successful prenatal diagnosis was made for 142 (98 for alpha thalassemia and 44 for beta thalassemia) out of 148 (95.9%) pregnancies at-risk for severe thalassemias. Twenty-three cases of hydrops fetalis, 4 of Hb H diseases and 14 of beta thalassemia were identified. All 41 pregnancies with affected fetuses were voluntarily terminated. Thus, this has led to a marked decrease of severe thalassemia syndrome since the program started.

CONCLUSIONWe presented the first community-based prospective screening program in China for control of alpha and beta thalassemia in Zhuhai city with a population of 1.29 million through premarital or prenatal screening. This model could be used for control of thalassemias and other hemoglobinopathies in other regions of China and also in other developing countries.

China ; Humans ; Prenatal Diagnosis ; methods ; alpha-Thalassemia ; diagnosis ; genetics ; beta-Thalassemia ; diagnosis ; genetics

OBJECTIVE: To perform genetic analysis, prenatal diagnosis and preimplantation genetic diagnosis (PGD) in a family with a rare deletional β- thalassemia. METHODS: Hematological parameters of the peripheral blood collected from all the family members were analyzed by whole blood cell analysis and capillary zone electrophoresis (CZE). Polymerase chain reaction-reverse dot blot (PCR-RDB) was used to identify 17 common β- thalassemia gene mutations, the multiplex ligation-dependent probe amplification (MLPA) and gap-polymerase chain reaction (gap-PCR) were used to identify β- globin gene cluster deletions. Chorionic villus sample or umbilical cord blood was obtained for prenatal diagnosis. Oligo-cells from blastocyst biopsy were collected for preimplantation genetic diagnosis by whole genome amplification and next generation sequencing. RESULTS: The proband was a carrier of Taiwanese deletion β- thalassemia, two fetuses were both thalassemia majors. The PGD results showed that 6 of 11 tested embryos could be choose for transplantation. CONCLUSION The Taiwanese deletion is a rare type deletion of β- globin gene cluster, and it can lead to thalassemia intermedia or thalassemia major when compounded with other β- globin gene mutation. PGD is another choice for thalassemia couples.
Female ; Genetic Testing ; Humans ; Pregnancy ; Preimplantation Diagnosis ; Prenatal Diagnosis ; alpha-Thalassemia ; beta-Thalassemia ; genetics

OBJECTIVE: To investigate the type and distritution of thalassemia gene mutaitons in Hunan area, so as to provide evidence for prenatal screening, diagnosis and reduction of birth defects. METHODS: A total of 5018 cases from Maternal and Children Health Hospital of Hunan from June 2017 to Dec 2018 were undergone thalassemia gene mutation analysis. The reverse dot blot hydridization was used to detect 6 kinds of genotypes of α-thalassemia and 17 kinds of point mutations of β-thalassemia, and the detected data were analyzed statistically. RESULTS: 889 cases (55.9%) of α-thalassemia carriers were found, including 385 cases of silent α-thalassemia, 488 cases of α-thalassemia trait, 16 cases of Hb H disease. --/αα was the most common genotype in α thalassemia. 664 cases (41.7%) were diagnosed as β-thalassemia carriers, heterozygotes accounted for 99.8% (663/664), IVS-Ⅱ-654, CD41-42M and CD17M were the main genotypes, and compound heterozygote accounted for 0.2% (1/664). 38 cases were diagnosed as α-thalassemia combined β-thalassemia. CONCLUSION The constituent ratio of thalassemia gene mutations in Hunan has regional characteristics, --/αα is the most common genotype in α-thalassemia carrier. IVS-Ⅱ-654, CD41-42 and CD17 are common ones in β-thalassemia. The frequency of α-thalassemia combined with β-thalassemia is high.
Child ; China ; Female ; Genotype ; Heterozygote ; Humans ; Mutation ; Pregnancy ; Prenatal Diagnosis ; alpha-Thalassemia ; genetics ; beta-Thalassemia ; genetics

OBJECTIVE: To investigate the common genotypes of thalassemia of the pregnant woman in Wuhan area of China, and to make the prenantal gentic diagnosis for the fetus at high risk of thalassemia. METHODS: A total of 357 pregnant woman with the primary positive screening in Wuhan area were included in this study. Genotypes were measured with PCR-flow cytometry, and fluorescence hybridization was used for detecting thalassmia gene. The husbands of the pregnant women with thalassmia were recalled for genetic analysis of thalassemia, and 9 cases of fetuses with high risk of thalassemia were detected by amniocontesis after genetic counseling. RESULTS: In 357 cases of the pregnant women in Wuhan area, the 214 cases were diagnosed as thalassemia, 80 cases were diagnosed as alpha thalassemia (up to 90%), whose genotypes were determind as --/αα (78.75%) and -α/αα (15.00%), while 133 cases were determind with genotype of IVS-2-654/N (43.61%), CD41-42/N (20.30%) and CD17/N (19.55%) in beta thalassemia (up to 80%). 9 prenatal diagnosis continued pregnancy included 1case of -α/--, 1 case of -α/αα, 2 cases of --/αα, 2 cases of IVS-2-654/N and 3 cases of normal, however, the pregnancy in prenatal diagnosis of -α/-- voluntarily was terminated after genetic counseling. Follow-up results after delivery were consistent with prenatal diagnosis. CONCLUSION Minor and static thalassemia were very common in Wuhan area. Genetic detection after primary screening, genetic counseling and prenatal diagnosis in pregnant women could provide a theoretical basis for the development of regional specific prevention of intermedius and critical thalassemia which is meaning for rearing and bearing better children.
China ; Female ; Genetic Testing ; Genotype ; Humans ; Pregnancy ; Prenatal Diagnosis ; alpha-Thalassemia ; beta-Thalassemia

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 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*