OBJECTIVE: To determine the carrier rate for thalassemia mutations in the ethnic Miao population of Qianxinan Prefecture. METHODS: Ethnic Miao people suspected for thalassemia trait at the People's Hospital of Qianxinan Prefecture, Guizhou Province between November 2020 to September 2024 were selected as the study subjects. Gap-PCR technology combined with high-throughput sequencing was used to screen a total of 666 individuals. ArcMap v10.8.2 was used to create a spatial distribution map of thalassemia based on the screening results. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2016-01). RESULTS: In total 254 positive cases were detected, with an overall positive rate of 38.14%. Among these, 173 cases were α-thalassemia (25.98%), 77 cases were β-thalassemia (11.56%), and 4 cases were αβ compound thalassemia (0.60%). The most common genotypes for α-thalassemia were αα/--^SEA (positive rate = 10.06%, accounting for 38.73%), αα/-α^3.7 (positive rate = 8.86%, accounting for 34.10%), and α^CSα/αα (positive rate = 4.95%, accounting for 19.08%). The most common genotypes for β-thalassemia were β^41/42(-TTCT)/β^A (positive rate = 5.11%, accounting for 44.16%) and β^{17 (A>T)}/β^A(positive rate = 4.20%, accounting for 36.36%), with these two genotypes accounting for as much as 80.52%. The spatial distribution map indicated that the highest overall detection rate of thalassemia and α-thalassemia in the Miao population of Qianxinan Prefecture was in Xingyi City. The highest detection rate of β-thalassemia was in Zhenfeng County, and the highest detection rate of αβ compound thalassemia was in Wangmo County. CONCLUSION The detection rate of thalassemia among the ethnic Miaos from Qianxinan Prefecture is relatively high, which primarily consisted of α-thalassemia. Regular monitoring and educational outreach should be conducted.
Humans ; China/ethnology* ; Female ; Male ; Genetic Testing ; Adult ; alpha-Thalassemia/genetics* ; Thalassemia/ethnology* ; Ethnicity/genetics* ; Genotype ; beta-Thalassemia/ethnology* ; Adolescent ; Mutation ; Middle Aged ; Child ; Asian People/genetics* ; Young Adult

OBJECTIVETo investigate the gene mutation spectrum of β-thalassemia in Dai ethnic population of 2 border region in Chinese Yunnan Province.

METHODSThe patients with β-thalassemia in Dai ethnic population of Dehong and Xishuangbanna autonamic prefecture were screened by using blood routine detection and capillary electrophoresis. The β-globin gene mutation in patients with β-thalassemia were detected by using PCR reverse dot-blot hybridization (PCR-RDB), the constitutive rate of gene mutation in patients with β-thalassemia of Dai ethnic population in two border regions was analyzed and compared.

RESULTSA total of 186 patients with gene mutation of β-thalassemia were confirmed. Among them, 10 gene mutation were found, and the 5 main gene mutations were CD26 (62.56%), CD41-42 (18.97%), CD17 (14.36%), CD71-72 (2.05%) and IVS-II-654 (1.54%). Among Dai ethinic population in Dehong region, 4 gene mutations were found including CD26 (80.31%), CD17 (11.02%), CD41-42 (6.30%) and CD71-72 (2.36%). Among Dai ethinic population in Xishuangbanna region, 6 gene mutations were found, out of them the more common gene mutations were CD41-42 (42.64%), CD26 (29.41%) and CD17 (20.59%).

CONCLUSIONThe gene mutations of β-thalassemia in Dai ethinic population of Yunnan province has been confirmed to be more genetic heterogenicity, the spectrums of β-thalassemia mutations in Dai ethinic population of different regions were significant different.

Antigens, CD ; genetics ; Asian Continental Ancestry Group ; China ; DNA Mutational Analysis ; Electrophoresis, Capillary ; Ethnic Groups ; Genetic Therapy ; Humans ; Mutation ; Nucleic Acid Hybridization ; Polymerase Chain Reaction ; beta-Globins ; genetics ; beta-Thalassemia ; ethnology ; genetics

OBJECTIVETo investigate the common mutation spectrum of α- and β-thalassemia in Yunnan childbearing-aged population.

METHODSThe common mutation types of α- or β-globin genes were detected by multiple Gap-PCR and the PCR-reversed dot blotting, and the unknown mutation types were determined by DNA sequencing in DNA samples of hypochromic microcytic anemia patients and carriers who were confirmed to be positive by serologic screaning, then the mutation types of globin in Yunnan population were analyzed statistically.

RESULTSA total of 40 kinds of mutation types were detected in 685 detected persons, among them the 3 commonest mutation types of α-globin genes were --(SEA)/αα (49.09%), -α(3.7)/αα (36.67%) and α(CS)α/αα (8.79%), the 3 commonest genetypes of β-globin gene were CD26(GAG>AAG)/N (43.78%), CD41-42(-CTTT)/N (20.1%) and CD17(AAG>TAG)/N (18.9%). There were 348 Han and 212 Dai ethnic persons in 685 cases, but their mutation of globin genes were different between these 2 ethnic groups. The results also showed that the gene mutation types were mostly concentrated in Dai ethnic individuals, since 28 of 38 detected α-β-thalassemia cases were Dai ethnic individuals.

CONCLUSIONThe mutation spectrums of α- and β-globin genes in Yunnan childbearing-aged population are diverse and different from that in other areas of China.

Alpha-Globulins ; genetics ; Anemia, Hypochromic ; ethnology ; genetics ; Asian Continental Ancestry Group ; China ; DNA Mutational Analysis ; Ethnic Groups ; genetics ; Genetic Testing ; Heterozygote ; Humans ; Mutation ; Polymerase Chain Reaction ; alpha-Thalassemia ; ethnology ; genetics ; beta-Globins ; genetics ; beta-Thalassemia ; ethnology ; genetics

OBJECTIVETo analyze the genotype-phenotype correlation among carriers from Guangdong with co-inherited hemoglobin Hb Westmead (HbWS) and β-thalassemia.

METHODSTwenty three patients (including 9 males and 14 females, aged 1-53 year old) were diagnosed by hematological analysis and genetic testing. Complete blood cell count and hemoglobin electrophoresis analysis were performed on a XE4000i automatic hemocyte analyzer. Hb, HbF and HbA2 were tested by high performance liquid chromatography (HPLC). Gap-PCR was adopted to detect three common thalassemia deletions. Reverse dot-blotting (RDB) assay was applied for detecting three common non-deletional α2 gene mutations and β-thalassemia.

RESULTSAmong the 23 patients, 12 showed anemia, among whom 9 had mild anemia and 3 had moderate anemia. The lowest Hb was 68 g/L, and both mean corpuscular volume and mean corpuscular hemoglobin were lower than average, while HbA2 was higher than 3.5%. Genetic analysis confirmed that 5 cases had αWS-α/α-α, β CD654/β N (21.7%), 4 had α WS-α/α-α, β CD41-42/β N (17.4%), 5 had α WS-α/α-α, β CD17/β N (21.7%), 4 had α WS-α/α-α, β CD28/β N (17.4%), 1 had α WS-α/α-α, β CD71-72/β N (4.3%), 1 had αWS-α/α-α, β CD27-28/β N (4.3%), 1 had α WS-α/α-α, β CD41-42/β CD17 (4.3%), 2 had a concomitant β-thalassemia heterozygosity and -α 3.7 deletion.

CONCLUSIONPatients with co-existing Hb WS and other β-thalassemia trait may show variable clinical features. Such compound heterozygotes are usually misdiagnosed during screening by hemoglobin electrophoresis, accurate diagnose should be attained by molecular diagnosis.

Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; Child ; Child, Preschool ; China ; DNA Mutational Analysis ; Erythrocyte Indices ; Female ; Genetic Association Studies ; methods ; Genotype ; Hemoglobins ; genetics ; metabolism ; Hemoglobins, Abnormal ; genetics ; Humans ; Infant ; Male ; Middle Aged ; Phenotype ; Polymerase Chain Reaction ; methods ; Young Adult ; beta-Thalassemia ; blood ; ethnology ; genetics

OBJECTIVETo investigate the spectrum of β -thalassemia mutations in Guizhou Province.

METHODSFor 542 individuals suspected to have β -thalassemia by decreased mean corpuscular volume (MCV) and corpuscle hemoglobin (MCH) by routine blood test and hemoglobin electrophoresis, reverse dot blot hybridization (RDB) was performed to detect 17 known β -thalassemia mutations, including 8 common and 9 rare mutations. For cases where no mutation was identified, the entire human β -globin gene was screened to find other rare mutations. The distribution and frequencies of detected β -thalassemia mutations were then analyzed.

RESULTSA total of 460 individuals were diagnosed as β -thalassemia by DNA analysis, which included 352 heterozygotes, 67 compound heterozygotes and 41 mutant homozygotes. A total of 12 β -thalassemia mutations were detected in these individuals. The mutations have ranked from high to low frequency as: CD17 (40.74%), CD41-42 (33.69%), IVS-II-654 (13.76%), -28 (3.70%), β E (3.35%), CD71-72(1.94%), CD43 (1.06%), IVS-I-1 (0.71%), CD27-28 (0.35%), -29(0.35%), CAP (0.18%), and CD121 (0.18%). The former six mutations have accounted for 97.18% of all. CD121 (GAA> TAA) detected from a heterozygote, as a dominant mutation, has been firstly found in the Chinese population.

CONCLUSIONThe spectrum of β -thalassemia in Guizhou Province showed certain distinct characteristics, with CD17 being the most common mutation. The newly discovered mutation of CD121 has expanded the spectrum of β -thalassemia in Chinese population. Our result may provide valuable information for the prevention and control of β -thalassemia in Guizhou.

Adolescent ; Adult ; Asian Continental Ancestry Group ; genetics ; Child ; Child, Preschool ; China ; DNA Mutational Analysis ; Female ; Humans ; Infant ; Leukosialin ; genetics ; Male ; Middle Aged ; Mutation ; Platelet Membrane Glycoprotein IIb ; genetics ; Receptors, Interleukin-1 Type I ; genetics ; Young Adult ; beta-Globins ; genetics ; beta-Thalassemia ; diagnosis ; ethnology ; genetics

OBJECTIVETo investigate the incidence and the gene mutation frequencies and patterns of β-thalassemia (β-Thal) in ethnic Han children in Chongqing city.

METHODA total of 1726 children were screened by using automatic hemocytic analyzer, cellulose acetate electrophoresis and fetal hemoglobin alkali denaturation test. Samples with mean corpuscular volume (MCV) < 80 fl, cell hemoglobin content (MCH) < 27 pg and hemoglobin A2 (HbA2) levels >3.3%, fetal hemoglobin (HbF) >2% for &beta;-Thal screening indicators. The positive samples of screening indicators were detected and identified by PCR-reverse dot blot method for 18 common &beta;-Thal mutations in Chinese populations, unknown mutations samples were subjected to DNA sequencing analysis of the &beta;-globin gene.

RESULTTwenty-five cases of &beta;-Thal carriers were observed from the 1726 samples, with 24 cases of &beta;-Thal heterozygote and one case of double heterozygote. Therefore, the &beta;-Thal carrier rate was 1.51%. After 1726 peripheral venous blood samples analyzed by hematological parameters, 164 positive cases of &beta;-Thal screening indicators were found, with the positive rate being 9.50% (164/1726). A total of 6 different gene mutations were detected, the four most common mutations were as the following: CD41-42, IVS-II-654, CD17 and beta E. These four mutations as the major types in this area accounted for 88.00% of all the mutations. In addition, one rare mutation of 5 'UTR; + (43 -40) was found, and one case of the hemoglobin variant of Hb Zurich was reported in Chinese people for the first time.

CONCLUSIONChongqing is a high risk region of the &beta;-Thal. Epidemiological Data from the research was useul for the genetic counseling and the prevention of &beta;-Thal major.

Asian Continental Ancestry Group ; genetics ; Blood Chemical Analysis ; Child ; Child, Preschool ; China ; epidemiology ; Female ; Gene Frequency ; Genetic Counseling ; Hemoglobins ; analysis ; genetics ; Hemoglobins, Abnormal ; analysis ; genetics ; Heterozygote ; Humans ; Infant ; Male ; Mutation ; genetics ; Prevalence ; beta-Globins ; genetics ; beta-Thalassemia ; epidemiology ; ethnology ; genetics

OBJECTIVETo investigate the carrier rate of thalasaemia among the children of 10 minority ethnic groups in 3 border states (Xishuangbanna, Dehong and Nujiang) of Yunnan Province.

METHODSA total of 6562 samples of children under 10 years old were analyzed by blood cell automatic analysis and hemoglobin electrophoresis.

RESULTSThe overall carrier frequency of thalasaemia was highest (46.2%) in Dehong, and lowest (30.6%) in Nujiang. The carrier frequency of beta-thalasaemia was the highest (40.6%) in Achang, and lowest (2.5%) in Dulong. The carrier frequency of alpha-thalasaemia was the highest (22.1%) in Dai from Xishuangbanna, followed by Dulong (19.1%).

CONCLUSIONThalasaemia carrier rates were high among the children of 10 minority ethnic groups in Yunnan. There were regional differences in their incidences. The results provide a valuable basis for thalasaemia prevention in Yunnan minorities in the three border states.

Child ; Child, Preschool ; China ; epidemiology ; Hemoglobins, Abnormal ; genetics ; Humans ; Infant ; Infant, Newborn ; Minority Groups ; Prevalence ; Thalassemia ; ethnology ; genetics ; alpha-Thalassemia ; epidemiology ; genetics ; beta-Thalassemia ; epidemiology ; genetics

OBJECTIVETo investigate the gene mutation frequencies and patterns of &beta;-thalassemia (&beta;-thal) in the minority populations of Guizhou province.

METHODSThree thousand and five hundred couples in the reproductive age were screened by using automatic hemocyte analyzer and hemoglobin autoanalyzer-variant. The diagnostic criteria for &beta;-thal were: the mean corpuscular volume (MCV) was ≤ 82 fl, and the HbA(2) level was ≥ 3.5%. A total of 194 positive samples were detected and further identified by PCR-reverse dot blot (PCR-RDB) assay for 18 common &beta; -thal mutations in Chinese population. Those subjects with positive phenotypes but without the 18 common &beta;-thal mutations were subjected to DNA sequence analysis of the &beta;-globin gene.

RESULTSOne hundred and eighty-nine samples with gene mutations were observed from the 3500 samples, with the incidence of &beta;-thal being 5.4%. A total of 10 different &beta;-thal mutations were identified from the 189 diagnosed samples. The five most common mutations were as the following: CD17 (43.9%), CD41-42 (38.6%), IVS-II-654(10.1%), -28 (2.6%) and CD71-72 (1.6%). In addition, a novel &beta;-globin gene mutation (-CD53) allele was detected. One rare mutation of IntM was observed.

CONCLUSIONThe minority population in Guizhou province is of high risk of &beta;-thal. It is recommended that more attention should be paid to detect the carriers of &beta;-thal in the population in reproductive age by hematologic screening and common gene diagnosis in the area with high risk of &beta;-thal.

Adult ; Base Sequence ; China ; ethnology ; DNA Mutational Analysis ; Ethnic Groups ; genetics ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Young Adult ; beta-Globins ; genetics ; beta-Thalassemia ; genetics

OBJECTIVETo establish an improved, simple and convenient megaprimer PCR method for site-directed mutagenesis(SDM).

METHODSThis protocol is based on the design of two different plasmid DNA templates. Template 1 lacks the binding site for reverse flanking primer, and template 2 lacks the binding site for forward flanking primer. This modification avoids amplification of full-length wild-type sequences while two templates, the forward and reverse flanking primers exist simultaneously in one reaction tube. A megaprimer is synthesized in the first PCR reaction using template 1, forward primer and mutagenic primer. The megaprimer that needn't the cumbersome gel purification step is directly added to the second PCR reaction system. The second PCR reaction(PCR 2) containing two stages is performed using template 2, megaprimer, forward and reverse flanking primer. During the first stage of PCR 2, the megaprimer is extended to form the full-length mutation product. In the second stage of PCR 2, the extended megaprimer containing SDM residues is subsequently amplified with the two flanking primers. All of the final PCR products contained the desired mutation.

RESULTSFifteen types of rare beta-thalassemia mutations in Chinese were obtained using this method. Each of these modified fragments was separately cloned into the pGEM-T vector and sequenced. The desired mutations involved in mutagenesis amplicons were identified in all clones.

CONCLUSIONThis improved PCR-based megaprimer method for site-directed mutagenesis is rapid, simple and highly efficient, and the success rate of mutagenesis could reach 100%. Furthermore, this method is suitable for routine application in molecular cloning.

Asian Continental Ancestry Group ; genetics ; DNA Primers ; Globins ; genetics ; Humans ; Mutagenesis, Site-Directed ; Polymerase Chain Reaction ; methods ; beta-Thalassemia ; ethnology ; genetics