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We report the molecular and hematological identifications of two novel δ-globin gene mutations found in Guangxi Zhuang Autonomous Region, China. Capillary electrophoresis of the proband showed 1.3% Hb A2, accompanied by a minor unknown peak (0.7%) within the Z1 zone. High-performance liquid chromatography also revealed the presence of 1.5% Hb A2 and a 0.6% unknown peak. Routine genetic testing (Gap-PCR and reverse dot-blot hybridization) for common α-thalassemia was performed, and no mutations were observed. Sanger sequencing identified a heterozygous mutation for GAC > AAC at codon 79 (HBD:c.238G > A) and G > A at polyA + 70 (HBD:c.*200G > A) of the δ-globin gene. This variant was named Hb A2-Guangxi [δ79 (EF3) Asp→Asn, HBD:c.238G > A] after the geographic origin of the proband. [ABSTRACT FROM AUTHOR]

We report a new δ-chain hemoglobin (Hb) variant observed in a 5-year-old female living in Yulin, Guangxi, China. Capillary electrophoresis revealed splitting of the Hb A2 peak into two fractions (Hb A2 and Hb A2 variant), and the Hb A2 variant was also detected by high-performance liquid chromatography. However, it could not be detected using matrix-assisted laser desorption lonization-time of flight mass spectrometry. CD41-42 (-TCTT) heterozygosity was observed on the HBB gene by PCR and reverse dot-blot hybridization. Sanger sequencing showed a new transition (G > A) at codon 46 of the HBD gene, resulting in glycine changing to arginine. Based on the patient's place of residence, the new variant was named Hb A2-Yulin [δ46(CD5)Gly→Arg,HBD:c.139G > A]. [ABSTRACT FROM AUTHOR]

δβ-thalassemia is a rare type of thalassemia characterized by increased Hb F levels, including mainly Chinese Gγ(Aγδβ)0-thalassemia, Yunnanese Gγ(Aγδβ)0-thalassemia, Cantonese Gγ(Aγδβ)0-thalassemia in China. Due to the low rate of δβ-thalassemia carriers, there are few reports of δβ-thalassemia combined with β-thalassemia causing β-thalassemia major. Herein, we described the combination of Chinese Gγ(Aγδβ)0-thalassemia and β-thalassemia leading to β-thalassemia major in a Chinese patient. Hemoglobin analysis was performed by capillary electrophoresis (CE). Routine genetic analysis was carried out by gap-polymerase chain reaction (Gap-PCR) and PCR and reverse dot blot (PCR-RDB). Multiple ligation-dependent probe amplification (MLPA) was used to detect the large deletion, and Gap-PCR confirmed the deletion. A CE result showed an elevated Hb F level of 98.7% and 11.7% in the proband and her mother, but the proband was diagnosed with βCD17M/βCD17M using routine genetic analysis. However, her father was heterozygous for CD17 in β-globin, and her mother was detected as SEA heterozygous. The further analysis presented that the proband had actually missed the diagnosis of Chinese Gγ(Aγδβ)0-thalassemia by MLPA and PCR-RDB. Finally, the genotype of the proband was corrected from βCD17M/βCD17M to βCD17M/βGγ(Aγδβ)0. This is the first report of Chinese Gγ(Aγδβ)0-thalassemia combined with β-thalassemia resulting in β-thalassemia major in China. Screening for δβ-thalassemia by Hb analysis could be an effective method. [ABSTRACT FROM AUTHOR]

We report a novel hemoglobin (Hb) variant found in a 34-year-old Chinese male during a routine measurement of glycated hemoglobin. The variant resulted in a P3 peak of 27.5% of the total Hb on high performance liquid chromatography (HPLC) with a glycated hemoglobin mode. However, no abnormal Hb peaks were observed in capillary electrophoresis (CE) with 3.1% Hb A2 and 96.9% Hb A. The amino acid substitution was determined by Sanger sequencing as α20 (B1) His→Leu; the corresponding DNA mutation was identified as CAC > CTC at the first position of codon 20 of the α-chain. This is the first description of the mutation, and we have named it Hb Hebei for the region of origin of the proband. [ABSTRACT FROM AUTHOR]

We report a novel mutation on the β-globin gene in a female of the Chinese population. This mutation produces a β-globin variant that can be detected by the capillary electrophoresis (CE) method, but coelutes with Hb A2 by high performance liquid chromatography (HPLC). DNA sequencing showed a mutation of codon 46 and it was named Hb Cenxi [β46(CD5)Gly→Arg (GGG>CGG), HBB: c.139G>C] for the city of birth of the proband. She presented normal hematological parameters. [ABSTRACT FROM AUTHOR]

β-Thalassemia (β-thal) is a common hematological disorder in the Guangxi Zhuang Autonomous Region of Southern China. Heterozygous β-thal is usually associated with reduced hematological indices and increased Hb A2 levels. However, the preventive program of the regional government only conducts the screening of hematological indices [complete blood count (CBC)] especially at primary hospitals. In this study, we describe a male β-thal patient presenting normal hematological indices but with a high Hb A2 level. We proposed that hemoglobin (Hb) analysis and CBC should be performed together in the preventive screening program in regions with a high thalassemia incidence to avoid misdiagnosis. [ABSTRACT FROM AUTHOR]

Hb Constant Spring [Hb CS, α142, Term→Gln, TAA>CAA (α2)] is a nondeletional form of α-thalassemia (α-thal) that is most prevalent in Southern Chinese and Southeast Asian populations. We previously found that Hb CS trait could efficiently be screened using Sebia Capillarys2. In this study, we report that Hb CS heterozygotes combined with β-thal could not be detected by the Sebia Capillarys2 method due to the very small amount of Hb CS. [ABSTRACT FROM AUTHOR]

AbstractWe report a novel large α-globin gene cluster deletion in a Chinese family from the Guangxi Zhuang Autonomous Regionfor the first time. The proband was a 20-year-old male who presented with microcytic hypochromatosis. Routine genetic analysis showed none of the common mutations in theα-globin and β-globin genes. Multiplex ligation-dependent probe amplification (MLPA) of the α-globin chain revealed there was a large deletion, which removed the entire HBA2 and HBA1 genes, HBQ gene, HBZ gene, and major regulatory element HS-40, eliminating more than 134 kb from the α-globin chain. Subsequently, pedigree analysis revealed that the proband inherited the novel deletion from his father. By consultation of literature and databases, it was confirmed as a hitherto undescribed chain deletion and named Laibin deletion (–LB) for the origin of the proband. [ABSTRACT FROM AUTHOR]

Hb A2 (α2δ2) is one of the key components looked for in hemoglobinopathies screening programs. Therefore, quantitative and accurate method for Hb A2 value determination is essential for routine screening. Here, we report a case of Hb A2 and Hb Constant Spring (Hb CS, HBA2: c.427T>C) with Hb H-Hb CS disease that was not detected by high performance liquid chromatography (HPLC), while Hb A2 and Hb CS were clearly quantified by capillary electrophoresis (CE). [ABSTRACT FROM AUTHOR]

We report a novel large α-globin gene cluster deletion in a Chinese family from the Guangxi Zhuang Autonomous Regionfor the first time. The proband was a 20-year-old male who presented with microcytic hypochromatosis. Routine genetic analysis showed none of the common mutations in theα-globin and β-globin genes. Multiplex ligation-dependent probe amplification (MLPA) of the α-globin chain revealed there was a large deletion, which removed the entire HBA2 and HBA1 genes, HBQ gene, HBZ gene, and major regulatory element HS-40, eliminating more than 134 kb from the α-globin chain. Subsequently, pedigree analysis revealed that the proband inherited the novel deletion from his father. By consultation of literature and databases, it was confirmed as a hitherto undescribed chain deletion and named Laibin deletion (- LB ) for the origin of the proband.