[Genotypic and Phenotypic Analysis of αß-Thalassemia in Children].

ABSTRACT

OBJECTIVE: To analyze the genotype and hematological characteristics of children with αß-thalassemia in Shenzhen area of China. METHODS: The erythrocyte parameters and hemoglobin components of the children were determined by blood routine examination and capillary electrophoresis (CE). Reverse dot blot (RDB) -polymerase chain reaction (PCR) was used to determine gene mutations in α- and ß-thalassemia children. The Gap-PCR was used to determine the gene deletion of α-thalassemia children，while specimens suspected HKαα were determined with nested PCR. RESULTS: Total of 29 complex genotypes were detected from 74 cases of αß-thalassemia, among which 1 case was determined as ß-thalassemia with αααanti4.2/αα and 5 cases were double heterozygous ß-thalassemia combining α-thalassemia with intermediate phenotype. 1 case of ß-28/ßcap+40-43 double heterozygotes combined with --SEA/αα and the other 62 cases were characterized by light ß-thalassemia, 2 cases ofßCAP+40-43/ßN with --SEA/αα showed light α-thalassemia. CONCLUSION: The genotypes of αß-thalassemia in Shenzhen area of China are complex and diverse. The common complex genotypes are similar to those of simple ß-thalassemia. If the genotype and phenotype are not consistent, the existence of rare genotype should be considered.