ABSTRACT
Objective To investigate the incidence and the types of gene mutations of α-thalassemia in the child-bearing pop-ulation of Conghua District,Guangzhou.Methods Blood samples from 24 083 people of childbearing age were screened by blood cell analysis and hemoglobin electrophoresis,α-globin gene variation was detected by GAP-PCR and PCR reverse dot blot in the positive cases,and 17 common β-globin gene mutations were detected by PCR reverse Dot blot.Results A total of 2 596 cases of α-thalassemia gene abnormality were detected by gene identification,and the abnormal rate was 10.78%.A sum of 170 cases(0.71%)had a compound mutation of α-β gene.There were 2 550 cases(98.23%)of deletion and 46 cases(1.77%)of non-deletion in the mutant genes.There were 14 types of gene mutation,including 5 types of HbH disease(with--SEA/-α3.7 primarily),4 mild types(with 68.61%of--SEA/αα genotype),and 5 quiescent types(the top two genotypes were-α3.7/αα and-α4.2/αα).A total of 23 types of αβ complex gene mutation were detected,and the top six types were--SEA/βCD41-42,-α3.7/βCD41-42,--SEA/β654,--SEA/-28,-α3.7/β654 and-α3.7/βCD17,which accounted for 75.27%of all the complex types.Conclusion The gene abnormality rate of α-thalassemia in Conghua District of Guangzhou City was high.The gene mutation type and constitu-ent ratio,which have their own characteristics,is a special region of α-thalassemia.