云南省德宏地区产前诊断中地中海贫血基因分析

Genetic analysis of thalassemia in prenatal diagnosis in Dehong area of Yunnan Province

目的探讨地中海贫血高发区云南德宏地区孕妇地贫基因分布情况,为地贫高发地区的疾病防控策略制定和遗传咨询提供参考依据。方法采用液相芯片技术对德宏州人民医院的8928例孕妇进行地贫基因筛查,并根据筛查结果进行产前诊断,通过羊膜穿刺术对104例孕妇进行羊水检测以及遗传咨询。结果8928例孕妇样本中检出2443例(27.36%)携带地贫基因突变类型,其中包括CD41(-C)罕见突变类型2例。104例孕妇羊水检测中,85例(81.73%)胎儿携带有地贫基因突变,其中重型α-地贫和重型β-地贫共6例(5.77%),中间型地贫共23例(22.11%)。经遗传咨询,所有重型地贫以及部分中间型地贫的孕妇自愿终止妊娠。结论云南德宏地区孕妇中地贫基因突变携带率较高,高风险孕妇的胎儿中存在较高比例的中度和重度地贫基因型。对育龄人群进行基因筛查以及对高风险家庭进行产前诊断和遗传咨询,是减少重症地贫患儿出生及降低地贫疾病负荷的有效防控策略。

Objective To analyze the genetic distribution of thalassaemia in pregnant women and the genetic diagnosis of fetuses of the couple with thalassaemia gene in Dehong region of Yunnan Province, which is a high incidence area of thalassaemia, and to provide basic reference data for control and genetic counselling of thalassaemia. Methods In this study,8928 pregnant women in People’s Hospital of Dehong Dai and Jingpo Autonomous Prefecture from were screened for thalassemia gene using liquid chip technology. If the screening result of woman was positive, her spouses were screened as well.Amniocentesis was taken for genetic counselling by 104 Pregnant women whose fetus had thalassaemia risk. Results 24 genotypes of thalassemia including CD41(-C) rare mutation in 2443 cases were detected in 8928 samples, the detection rate of thalassemia mutation was 27.36%. 85 cases with mutations were detected in the 104 pregnant women’s amniotic fluid, the detection rate was 81.73%, which including 3 cases of severe α-thalassemia, 15 cases of intermediate type α-thalassemia HBH,3 cases of severe β-thalassemia, and 8 cases of intermediate type β-thalassemia. By genetic counselling, all pregnant women with severe thalassemia fetus and some with intermediate thalassemia fetus voluntarily terminate pregnancies. Conclusion Pregnant women in Dehong area of Yunnan Province have a high mutation carrying rate of thalassemia. Screenings for women of childbearing age and prenatal diagnosis for high-risk families are effective strategies for thalassemia prevention and control to reduce the birth of children with severe thalassemia.