Abstract: OBJECTIVE: To explore the gene mutation types and proportions of non-deletion α-thalassemia, and to provide clinical basis for genetic counselling. METHODS: The gene mutation types and frequencies of 259 suspected non-deletion α-thalassemia patients were analyzed by Gap-PCR and PCR-RDB. 30 pregnant women whose husband had the same type of thalassemia received thalassemia prenatal diagnosis. We completed follow-up works. RESULTS: Among the 259 cases, 170 cases of αα^QS/αα, 43 cases of αα^WS/αα, 34 cases of αα^CS/αα, 6 cases of——^SEA/αα^QS, 4 cases of——^SEA/αα^CS, one case of -α^3.7/αα^QS, and one case of -α^4.2/αα^QS were found. Compared with normal control group, there were statistical significances in MCV, MCH in different types of non-deletion α-thalassemia (P<0.05). 5 fetuses with non-deletion HbH disease were confirmed by prenatal diagnosis. The results of postpartum follow-up were consistent with prenatal diagnoses. CONCLUSION: Guangzhou is a high incidence area of non-deletion α-thalassemia. The most common genotype is αα^QS/αα. To reduce the birth of children with non-deletion HbH disease, non-deletion thalassemia genotype carriers should be tested.

Key words: non-deletion α-thalassemia, mutation, gene diagnosis, prenatal diagnosis