Genotypic characteristics of thalassemia and evaluation of the effectiveness of blood routine screening in Sanya City
10.3760/cma.j.cn231583-20220225-00045
- VernacularTitle:三亚市地中海贫血基因型特征及血常规筛查效果评估
- Author:
Xiujuan TIAN
1
;
Meihua TAN
;
Ting SUN
;
Shiping CHEN
;
Bo JIAO
;
Chunrong HUANG
;
Liting CHEN
;
Dan XIE
;
Ying YU
Author Information
1. 上海交通大学医学院附属上海儿童医学中心海南医院产前诊断中心，海南 572000
- Keywords:
Thalassemia;
Genetic screening;
Genotype;
Blood routine
- From:
Chinese Journal of Endemiology
2023;42(9):710-715
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To analyze the mutation types and distribution characteristics of thalassemia gene among high-risk populations in Sanya City, and to evaluate the effectiveness of blood routine screening, in order to provide scientific basis for formulating measures for prevention and control of thalassemia in Sanya City.Methods:Retrospective analysis was used to collect detection results and clinical data from high-risk individuals who completed genetic screening for thalassemia at Sanya Materal and Child Health Hospital from January 2019 to August 2021. Mutation types and distribution characteristics of thalassemia gene were analyzed, and the missed detection rate and sensitivity of blood routine indicators [mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH)] were evaluated based on the results of genetic screening for thalassemia.Results:A total of 5 760 high-risk individuals were included in the screening results of thalassemia genes, and 3 868 samples of thalassemia gene mutations were detected, with a detection rate of 67.15%. Among them, there were 2 979 samples with α-thalassemia genetic mutations, with a detection rate of 51.72%; including 2 966 common genotype samples (99.56%), the main genotype was αα/-α 3.7 (20.14%, 600/2 979); 13 rare genotype samples (0.44%), 4 cases of αα/-- THAI, 3 cases of α CD40(AAG>AA-)α/αα, 2 cases of α PPα/αα, and 1 case of Fusion gene/αα, Fusion gene/α WSα, α WSα/α PPα, and α CD40(AAG>AA-)α/α WSα each. There were 340 samples with β-thalassemia gene mutations, with a detection rate of 5.90%; including 336 common genotype samples (98.82%). The β CD41/42/β N genotype was dominant (57.65%, 196/340); 4 rare genotype samples (1.18%), β CD5(-CT)/β N, β IVS-Ⅱ-2(-T)/β N, β IVS-Ⅱ-761(-T)/β N and β Initiation(ATG>AGG)/β N 1 case each. There were 549 samples of αβ-compound type thalassemia, with a detection rate of 9.53%. The α missing recombination β CD41/42 genotype was dominant (61.02%, 335/549). There were a total of 4 226 samples that could be traced back to MCV and MCH. Among them, 3 007 samples were found to have mutations in thalassemia genes through screening, 2 584 cases were found to have abnormalities in the combination of MCV and MCH indicators, and 423 samples were missed in blood routine screening, with a missed detection rate of 14.07% (423/3 007). The missed samples were mainly α static type, accounting for 89.13% (377/423) of the total missed samples. The screening sensitivity of MCV combined with MCH for α-, β- and αβ-compound type thalassemia was 82.65%, 98.07% and 98.15%, respectively. Conclusion:The types of genetic mutations in thalassemia in Sanya City are complex and diverse, and there are certain omissions in the blood routine screening of MCV combined with MCH.
