Genetic testing of thalassemia in pregnant women in Ningbo City and analysis of changes of erythrocyte parameters in early pregnancy / 中华地方病学杂志

ABSTRACT

Objective:To study the results of thalassemia gene detection and prenatal diagnosis in pregnant women in Ningbo City, and analyze the characteristics of erythrocyte parameters in early pregnancy.Methods:A total of 636 suspected thalassemia pregnant women treated in Ningbo Women and Children's Hospital from January 2019 to September 2021 were selected as the research subjects, the dry blood spots of pregnant women were collected for thalassemia gene detection; and the amniotic fluid of pregnant women with thalassemia gene carried by both husband and wife was extracted for prenatal diagnosis, and the results of thalassemia gene detection and prenatal diagnosis were analyzed. Meanwhile, in the medical record system of Ningbo Women and Children's Hospital, the detection results of erythrocyte parameters in early pregnancy of pregnant women with thalassemia gene (thalassemia group) and healthy pregnant women (control group) were investigated. Erythrocyte parameters including hemoglobin (Hb), red blood cell count (RBC), mean corpuscular hemoglobin concentration (MCHC), mean corpuscular hemoglobin content (MCH), mean corpuscular volume (MCV), hematocrit (HCT) and red blood cell distribution width (RDW) were compared between groups and among different thalassemia gene variants.Results:Among 636 suspected thalassemia pregnant woman, 254 cases (39.94%) were confirmed thalassemia gene carriers, including 114 cases of α-thalassemia, 132 cases of β-thalassemia, and 8 cases of αβ-compound thalassemia. After genetic counseling, 11 women finally received prenatal diagnosis, 7 fetuses (7/11) were found to carry thalassemia gene, including two cases of -- SEA/αα and β CD17/β N, respectively; one case of β CD26/β N, αα/-α 3.7 and β CD41-42/β CD41-42, respectively. The results of erythrocyte parameters detection showed that compared with the control group ( n = 80), there were statistically significant differences ( P < 0.05) in various erythrocyte parameters in α-thalassemia group ( n = 77) and β-thalassemia group ( n = 87); and there were significant differences ( P < 0.05) in Hb, HCT, MCV, MCH and MCHC among the four major genotypes (-- SEA/αα, β IVS-Ⅱ-654/β N, β CD17/β N and β CD41-42/β N). Conclusions:The genetic testing of thalassemia in pregnant women in Ningbo City is mainly α-thalassemia or β-thalassemia, and prenatal diagnosis is necessary for pregnant women carrying thalassemia gene. The erythrocyte parameters in early pregnancy of pregnant women carrying thalassemia gene are changed, and there are differences among different genotypes.