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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 (-α3.7, -α4.2), 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 ααQS/αα was 100%, -α3.7/αα, -α4.2/αα, ααCS/αα and ααWS/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.
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Adult , Pregnancy , Female , Humans , alpha-Thalassemia/diagnosis , Genotype , Mutation , Erythrocyte Indices , Polymerase Chain Reaction , China , beta-Thalassemia/geneticsABSTRACT
Objective:To analyze the relationship between hematological and genotype characteristics of fetuses and patients with hemoglobin (Hb) H disease and their natural disease progression.Methods:From 2010 to 2022, a total of 1 252 blood samples from fetuses and patients with Hb H disease who visited the Guangxi Zhuang Autonomous Regional Maternal and Child Health Hospital were collected (including 174 umbilical cord blood samples, 1 062 peripheral blood samples from patients over 2 years old, and 16 peripheral blood samples from patients with rare cases of genotype Hb H). Additionally, 278 peripheral blood samples were collected from patients aged 0 - 2 years old with Hb H 3.7, Hb H 4.2, Hb H CS, and Hb H WS disease for the study of trends in red blood cell development. Multiple probe hybridization and microarray comparative genomic hybridization technology combined with first-generation Sanger sequencing were used for rare mutation detection.Results:Among the 1 062 Hb H disease patients over 2 years old, 62.34% (662/1 062) had gene deletion (--/-α), of which Hb H 3.7 (-- SEA/-α 3.7) and Hb H 4.2 (-- SEA/-α 4.2) were the most common, accounting for 42.28% (449/1 062) and 19.11% (203/1 062) of the total, respectively. Among the non-deletion genotypes (--/αα T or α Tα/αα T), Hb H CS (-- SEA/α CS), Hb H WS (-- SEA/α WS) and α CSα/α CSα accounted for 16.85% (179/1 062), 16.48% (175/1 062) and 1.98% (21/1 062), respectively. The 81.12% (537/662) of patients with deletional Hb H disease showed mild to moderate anemia, with Hb H detection rates ranging from 75% to 80%. Among non-deletional Hb H disease, Hb H WS disease showed the mild (blood Hb concentration > 95 g/L in 90% of patients) phenotype while Hb H CS and Hb H QS (-- SEA/αα QS) patients had moderate to severe anemia, with Hb H detected in peripheral blood at higher levels than in other types of Hb H disease patients. Except for Hb H CS and Hb H QS, which did not show a significant increase in Hb A2 levels when complicated with β-thalassemia, Hb A2 levels were increased (> 3.5%) in all other types of Hb H disease patients. When Hb H disease was complicated with β-thalassemia, Hb H peaks were not detected in either type of Hb H disease. The results of red blood cell development trend detection showed that erythrocyte counts were elevated in patients with Hb H disease compared to their normal counterparts; whereas, blood Hb, mean erythrocyte volume (MCV) and mean erythrocyte hemoglobin content (MCH) were lower than in their normal counterparts ( P < 0.05) and decreased to the minimum at 6 months to 1 year of age. Patients with Hb H CS disease, as the most severe form of anemia, had the highest MCV values ( P < 0.001). The results of fetal cord blood with Hb H disease showed that α CSα/α CSα caused severe intrauterine anemia, followed by Hb H QS and Hb H CS. The content of Hb Bart's in umbilical cord blood was negatively correlated with the severity of anemia ( rs = - 0.58, P < 0.001). When Hb H disease was complicated with β-thalassemia, there was no significant improvement in fetal anemia, and the Hb Bart's content did not change significantly ( P > 0.05). In addition, Hb H 21.9 (-α 21.9kb/-- SEA) and Hb H 2.4 (-α 2.4/-- SEA) were common in patients with deletion rare Hb H. In patients with non-deletion rare Hb H, αα Amsterdam-A1/-- SEA and αα Hb G-Georgia/-- SEA were both first reported. Conclusions:There is heterogeneity in clinical manifestations of patients with different types of Hb H disease or same type of Hb H disease at different developmental stages. When patients with Hb H are complicated with β-thalassemia, the phenotype of patients with the deletion type is improved, while that of patients with the non-deletion type is not. Compared to normal individuals, patients with Hb H disease have lower blood Hb concentration, MCV and MCH, and more rapid physiological changes in red blood cells.
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Background: The World Health Organization (WHO) 2016 classification incorporated molecular subtyping in glioma, highlighting the diagnostic and prognostic significance. The study aims to determine the isocitrate dehydrogenase (IDH-1) gene, α-thalassemia/mental retardation syndrome X-linked (ATRX) gene, and tumor suppressor gene-53 (p53) mutation in glioma and their correlation with various clinical and radiological parameters.Methods: In this prospective observational study, histopathological slides of glioma (2017-2018), were analyzed for IDH-1, ATRX and p53 mutations and their correlation with various clinical and radiological parameters.Results: IDH-1 mutation was found in 48 (38.7%), ATRX loss in 38 (30.6%) and p53 mutation in 40 (32.5%) patients. The expression of IDH-1 was significantly higher (43.7%) in adults; however, no significant difference was seen with gender. Also 51.2% of patients, who presented with seizures, showed IDH-1 expression; and 27.7% of patients, who had neurological deficit also showed IDH-1 expression. IDH-1 expression was high in glioma located at insula (73.3%) and parietal lobe (71.4%); while ATRX loss was seen in glioma located at insula (80%). Intraventricular glioma characteristically lacks all three markers: IDH-1 expression, p53 overexpression and ATRX loss. IDH-1 expression and p53 overexpression was seen mainly in diffuse fibrillary astrocytoma, oligodendroglioma, anaplastic astrocytoma and glioblastoma.Conclusions: Molecular subtyping is of paramount importance in glioma management. IDH-1 mutation is commonly observed in adults and patients presenting with seizures. The duration of symptoms correlates with IDH-1 and ATRX mutations. Hypothalamic tumors lack all three mutations.
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Objective: To investigate the rare variant types of abnormal -α3.7 deletion band samples detected by commercial kits commonly used in thalassemia, and analyze their blood type phenotype, so as to provide reference for clinical consultation. Methods: Peripheral blood samples of 4 238 patients from June 2016 to September 2019 in Ruijin Hospital, Shanghai Jiao Tong University School of Medicine were collected for routine blood analysis. DNA was extracted from whole blood, and the common mutation genes of thalassemia were detected by gap-polymerase chain reaction (Gap- PCR) and reverse dot blot (RDB). Gap-PCR and Sanger sequencing were used to detect rare mutations of α-thalassemia. Results: A total of 109 cases of -α3.7 deletion band were detected by routine genetic testing for thalassemia, among which 15 cases had abnormal -α3.7 deletion band. Gap-PCR and Sanger sequencing showed that 14 cases were confirmed to contain Hong Kong αα (HKαα) gene and 1 case was NG_000006.1: g.34569_38382 del 3 812 bp rare deletion. The misdiagnosis rate of abnormal -α3.7 deletion bands by routine Gap-PCR test for thalassemia was 13.76%. Conclusion: Patients with abnormal -α3.7 deletion bands should be detected for further confirmation by testing rare type of α-thalassemia, which will help provide more accurate genetic diagnosis results and genetic counseling.
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<p><b>OBJECTIVE</b>To develop a rapid preimplantation genetic diagnosis method for -thalassemia SEA deletion based on blastocyst cell whole genome amplification (WGA) combined with short fragment Gap-PCR.</p><p><b>METHODS</b>Using multiple displacement amplification (MDA) WGA technique, we established a double-fluorescent PCR system of the housekeeping genes GAPDH and β-actin for WGA quality testing, and a genotyping PCR system of mutant and normal short sequences for α-thalassemia SEA deletion. The sensitivity and accuracy of this method for diagnosis of -thalassemia SEA deletion were evaluated by detecting lymphocyte samples containing different cell numbers from carriers of SEA deletion. The applicability of this method was evaluated by testing of 12 blastocyst biopsy samples.</p><p><b>RESULTS</b>Detection of lymphocyte samples with different cell numbers using the method developed in this study revealed no ADO in 3-cell samples, and the product quantity of WGA became stable for 4-cell samples. Genotyping of the 10 blastocyst biopsy samples with successful WGA showed a genotype of --/ in 5 samples and / in the other 5 samples, which were consistent with the verification results.</p><p><b>CONCLUSIONS</b>The method developed in this study is a complete testing process for 4-6 blastocyst biopsy cells to allow rapid, accurate, and cost-effective PGD genotyping of -thalassemia SEA deletion using short fragment gap-PCR.</p>
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Objective To investigate the genotype and mutation frequency of thalassemia in child patients of Shenzhen region so as to provide evidences for the gene diagnosis and genetic counseling of thalassemia.Methods A total of 1 206 child patients suspected with thalassemia were retrospectively analyzed.The gene deletion of α-thalassemia was detected by Gap-PCR.The point mutations of α-thalassemia and β-thalassemia were determined by reverse dot blot(RDB)-PCR.The specimens suspected with HKαα and rare gene mutations were determined with nested PCR and gene sequencing,respectively.Results The detection rate of thalassemia was 76.9％ (927/ 1 206).Among them,α-thalassemia accounted for 40.5％ (489/1 206),and--SEA/αα was the most common gene mutation(75.1％);β-thalassemia accounted for 33.7％ (406/1 206),and the main IVS-2-654 (C→T) and CDM1-42 (-TCTT) heterozygous mutations accounted for 35％ and 32.5％,respectively.In addition,there were 32(2.7％) β-thalassemia patients with α-thalassemia mutation,1 patient with HKαα/ααQS,1 α-thalassemia patient with CD61 (AAG→TAG)/--SEA and 1 β-thalassemia patient with CD5 (CCT→C).Conclusion The are complicated gene mutation types and rare gene mutations of thalassemia in child patients of Shenzhen region.
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Objective To investigate the association between the value of α-thalassemia minor and the outcomes in pregnant women.Methods A total of 445 pregnant women with α-thalassemia minor were selected as thalassemia group in the Pingguo County Maternal and Child Health Hospital of Guangxi from January 2011 to December 2015,with ratio of 1 ∶ 4 healthy pregnant women was randomly recruited as non-thalassemia group.Clinical characteristics and pregnancy outcomes of the two groups were retrospectively analyzed using methods including t test,x2 test,and logistic regression model and ROC curve.Results There were no significant differences noticed in factors as age,BMI,gestational age and educational level of the two groups.Hemoglobin of the thalassemia group was significantly lower than that of the non-thalassemia group (P＜0.001).Differences on parity,ethnicities or occupation were statistically significant.Results from univariate analysis showed that the proportions of low birth weight,small for date infant and 1 min Apgar score ＜7 were higher in the thalassemia group,but the ratio of adverse pregnancy outcomes was comparable on parameters as preterm birth,stillbirth,macrosomia.Findings from the unconditional logistic regression showed that pregnancy complicated with α-thalassemia minor appeared a risk for both newboms with low birth weight (aOR=2.29,95％CI:1.32-3.95) and small for date infant (aOR=2.11,95％ CI:1.16-3.84).The ROC curve showed that α-thalassemia minor combined with multiple indicators presented a certain predictive value on neonatal birth weight.Conclusion Pregnancy complicated with α-thalassemia minor was likely to increase the risk of birth weight loss in newborns,suggesting that prenatal care for pregnant women with thalassemia be strengthened,in order to reduce the incidence of adverse pregnancy outcomes.
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Objective To investigate the association between the value of α-thalassemia minor and the outcomes in pregnant women.Methods A total of 445 pregnant women with α-thalassemia minor were selected as thalassemia group in the Pingguo County Maternal and Child Health Hospital of Guangxi from January 2011 to December 2015,with ratio of 1 ∶ 4 healthy pregnant women was randomly recruited as non-thalassemia group.Clinical characteristics and pregnancy outcomes of the two groups were retrospectively analyzed using methods including t test,x2 test,and logistic regression model and ROC curve.Results There were no significant differences noticed in factors as age,BMI,gestational age and educational level of the two groups.Hemoglobin of the thalassemia group was significantly lower than that of the non-thalassemia group (P＜0.001).Differences on parity,ethnicities or occupation were statistically significant.Results from univariate analysis showed that the proportions of low birth weight,small for date infant and 1 min Apgar score ＜7 were higher in the thalassemia group,but the ratio of adverse pregnancy outcomes was comparable on parameters as preterm birth,stillbirth,macrosomia.Findings from the unconditional logistic regression showed that pregnancy complicated with α-thalassemia minor appeared a risk for both newboms with low birth weight (aOR=2.29,95％CI:1.32-3.95) and small for date infant (aOR=2.11,95％ CI:1.16-3.84).The ROC curve showed that α-thalassemia minor combined with multiple indicators presented a certain predictive value on neonatal birth weight.Conclusion Pregnancy complicated with α-thalassemia minor was likely to increase the risk of birth weight loss in newborns,suggesting that prenatal care for pregnant women with thalassemia be strengthened,in order to reduce the incidence of adverse pregnancy outcomes.
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Objective To analyze the genotype distribution characteristics in the patients with α-thalassemia and the relationship between hematological phenotype and genotype .Methods 209 cases of α-thalassemia in our hospital from August to October 2016 were selected and divided into the silence type group (58 cases) ,standard type group(138 cases) ,intermediate type group(4 cases) and non-deletion type group(9 cases) .Contemporaneous 25 subjects undergoing healthy physical examination were selected as the normal control group .The automatic capillary electrophoreses was adopted to detect HbA 2 .The hematological indicators of MCV , MCH and MCHC were detected by using the automatic blood cells analyzer .Results Among 209 cases ofα-thalassemia ,8 mutation genotypes were detected ,in which - - SEA/αα deletion type accounted for 66 .03% ,- α3 .7/αα deletion type accounted for 22 .97% .The levels of MCV ,MCH and MCHC in the silence type group ,intermediate type group ,standard type group and non-de-letion type group was significantly lower than that in the normal control group ,the difference was statistically significant ( P<0 .05) ,the HBA2 level in the intermediate type group was lower than that in the normal control group ,the difference was statisti-cally significant (P<0 .05) ,but the HbA2 level had no statisticval difference between the silence type group ,standard type group and non-deletion type group with the normal control group(P>0 .05) .Conclusion The gene mutation in the patients with α-thalas-semia in Luohu District of Shenzhenis City is dominated by the deletion type of - -SEA/αα.The hematological indicators such as MCV ,MCH and MCHC can serve as the combined screening indexes of α-thalassemia ,but for the patients with -α3 .7/ααgenotypeα-thalassemia ,there is the possibility of missed diagnosis .
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Objective To investigate the application of capillary electrophoresis by dried filter blood paper for screening of α-thalassemia in neonates .Methods The hemoglobin (Hb) of 46 718 cases of neonatal dried heel blood spots were analyzed by the capillary electrophoresis and the content of HbA ,HbF ,HbA2 and abnormal Hb were detected ,the phenotype cases which was screened positive were recalled for genetic analysis .Results A total of 2 598 cases of Bart hemoglobin (Hb Bart′s) positive were detected in 46 718 cases of neonatal heel blood dried blood spots .The screening positive rate was 5 .56% (2 598/46 718) .A total of 477 cases of α-thalassemia gene carriers were confirmed by genetic analysis in the 544 cases which were recalled .The coincidence rate of Hb Bart′s screening and genetic diagnosis was 87 .68% (477/544) .By analyzing the relationship between the clinical pheno-types and the content of Hb Bart′s ,we found the Hb Bart′s content gradually increased with the severity of clinical phenotype ,and the difference was statistically significant (P= 0 .000) .Conclusion There is a good consistency between the capillary electrophore-sis of dried filter blood paper and the genetic analysis .It could be determined α-thalassemia clinical type according to the Hb Bart′s content .
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Objective To analyze the genetic mutation patterns and the constituent ratio of α-thalassemia in Luzhou area and to investigate the clinical application value of the gene diagnosis .Methods The PCR method combined with DNA chip hybridization technique was adopted to conduct the gene detection and analysis on 116 cases of suspectedα-thalassemia .Results Among 116 sus-picious cases of α-thalassemia ,39 cases were found with genotypes of α-thalassemia ,the detection rate was 33 .62% .7 kinds of mu-tation genotypes were detected ,in which the deletion type of - -αSEA/ααaccounted for 41 .03% and the deletion type of -α3 .7/ααaccounted for 25 .64% .Conclusion The main gene mutation of α-thalassemia in Luzhou area is the deletion type of - -αSEA/αα. The gene diagnosis is an important criterion for definitely diagnosing α-thalassemia .
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Recent investigations have highlighted various mechanisms of interaction between the Plasmodium falciparum (P. falciparum) parasite and the host, which are important for the understanding of the well-known protective effect by haemoglobinopathies like Sickle Cell Trait and α-Thalassemia against incidence and severity of malaria. Attention must therefore be given in the first place to the modifications induced in red blood cells (RBC) by the parasite in order to survive and display its pathogenic action: in this context, both the production of novel transport pathways able to support the development of the parasite during the erythrocytic cycle (in a cell which has lost transport activities during maturation process) and the changes induced to the RBC actin cyto-skeleton are discussed. As for the mechanisms involved in protection from P. falciparum infection, they can be of genetic, molecular, immunological character as well as interactive, due to the interplay of different factors. Some protection is afforded by genetic changes preventing P. falciparum to survive and proliferate within the red cell: such changes may include variants of the “basigin” receptor for the parasite antigens and inhibition by HbS of parasite-induced red cell remodelling. P. vivax infection may also be reduced in Duffynegative heterozygotes. Genetic factors specifically interacting with the development of the infection are the sickle cell trait, the presence of foetal Haemoglobin (HbF), particularly in its pancellular distribution and genes associated with malaria resistance, identified by genome-wide linkage studies. Selective advantage of HbAS heterozygotes over HbS homozygotes in the clinical course of malaria can be explained by the so called “balanced polymorphism”. The presence of foetal haemoglobin (HbF) has also a protective effect, due to retardation of parasite growth in such situation: this is the rationale behind the attempts to reactivate HbF production in Sickle Cell Disease(SCD). Phagocytosis of infected red blood cells (RBC’s) has a significant protective effect by keeping a low level of parasitemia in HbAS subjects. Recent research also points to the role of modifications of RBC’s adherence to microvascular endothelium as an important factor in the pathogenesis of malaria and suggest that abnormal Hb’s like HbS and HbC as well as α-thalassemia can impair the adhesion of the parasite major ligand to host cells, thus limiting the sequestration of parasite –invaded red cells in many tissues and organs, like the brain. A special role in protection from malaria can be ascribed to molecular mediators, particularly a sequence involving haeme-oxygenase (HMO-1), which appears upregulated in transgenic sickle cell mice: the action of HMO-1 prevents the cytotoxic effect of free heme and is in turn mediated by carbon monoxide, which inhibits Hb oxidation and further release of haeme from haemoglobin. Immunological factors are important, as shown by the development of children immunity to malaria, a rapid process in the early years of age (anti-disease immunity) and a slower one later (anti-parasite immunity); of remarkable interest are the antibodies to variant surface antigens (VSA) expressed by the parasite: an association was actually found between HbAS and the presence of IgG anti-VSA responses. Tolerance to parasite infection seems possible as the presence of β-chain mutations like in HbSAD mice provides a reduced incidence of experimental cerebral malaria. The possible role of various types of interferon is also under scrutiny. An example of interactions between different pathways comes from very recent studies, as it has been found that a mutation in the FAS gene promoter encoding the protein C- 95 results in a reduction of severe malaria incidence; as C-95 promotes apoptosis, an effect due to a C-95 – aided killing of immune cells, thus preventing an excessive immune response, is an interesting case of molecular-immunological interplay. Moreover, recent data on the mechanisms of malaria resistance, , show that during the intraerythrocytic life cycle of P. falciparum, two microRNA (miRNA),highly enriched in HbAS and HbSS erythrocytes, become integrated into the parasite messenger RNAs and cause translational inhibition, thus acting as negative regulators of parasite growth. It appears therefore that a very peculiar host defense strategy is working in sickle cell erythrocytes through miRNA activity.