Dataset Information

Molecular analysis of alpha- and beta-thalassemia in Meizhou region and comparison of gene mutation spectrum with different regions of southern China.

ABSTRACT:

Background

Thalassemia is a group of inherited autosomal recessive hemolytic anemia disease caused by reduced or absent synthesis of globin chain/chains of hemoglobin. Only few studies showed the molecular characterization of α- and β-thalassemia in Meizhou city of China.

Methods

A total of 22,401 individuals were collected; hematological and hemoglobin electrophoresis analysis and thalassemia genetic testing were performed.

Results

Eleven thousand and thirty (49.24%) cases with microcytosis (mean corpuscular volume (MCV) < 82 fl), 11,074 (49.44%) cases with hypochromia (mean corpuscular Hb (MCH) < 27 pg) in 22,401 subjects, 11,085 cases with abnormal hemoglobin results were identified in subjects aged ≥6 months. 7,322 (32.69%) subjects harbored thalassemia mutations, including 4,841 (21.61%) subjects with α-thalassemia, 2,237 (9.99%) with β-thalassemia, and 244 (1.09%) with α-thalassemia combined β-thalassemia. 18 genotypes of α-thalassemia mutations and 27 genotypes of β-thalassemia mutations were characterized. The most frequent α gene mutation was --^SEA (64.69%), followed by -α^3.7 (19.93%), -α^4.2 (7.73%), α^CS α (3.97%), and α^WS α (2.83%). The six most common β-thalassemia mutations were IVS-II-654 (C>T) (39.79%), CD41-42 (-TCTT) (33.02%), -28 (A>G) (10.38%), CD17 (A>T) (9.08%), CD27-28 (+C) (2.14%), and CD26 (G>A) (2.02%). In addition, MCV and MCH were sensitive markers for α- and β-thalassemia except for -α^3.7 /αα, -α^4.2 /αα, α^CS α/αα, α^WS α/αα, and β^Cap+40-43 /β^N .

Conclusions

The --^SEA , -α^3.7 , and -α^4.2 deletions were the main mutations of α-thalassemia, while IVS-II-654 (C>T), CD41-42 (-TCTT), -28 (A>G), and CD17 (A>T) mutations of β-thalassemia in Meizhou. There were some differences in thalassemia mutation frequencies in Meizhou city from other populations in China.

SUBMITTER: Wu H

PROVIDER: S-EPMC8649333 | biostudies-literature |

REPOSITORIES: biostudies-literature

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