Analysis of Deletional Hb H Diseases in Samples with Hb A2-Hb H and Hb A2-Hb Bart's on Capillary Electrophoresis

摘要

The capillary electrophoresis (CE) system allows the quantification of Hb Bart's (y4) and Hb H (04) that is used for screening of Hb H disease. However, Hb Bart's hydrops fetalis and Hb H are not always codetected in patients with Hb H disease. In this study, 35 samples were analyzed for the ct°-thalas-semia (a°-thal) [-7SEA (Southeast Asian) and --THAI (Thailand)] deletions and the oc+-thal [-a37 (right-ward) and -a4'2 (leftward)] type deletions using real time-polymerase chain reaction (real time-PCR) with SYBR Greeni and high-resolution melting (HRM) analysis and conventional gap-PCR techniques, respectively. Results showed that 28 of 29 (96.6%) samples with the Hb A2-Hb H phenotype on CE elec-trophoregrams presented the genotype of --S￡A/-a? , while the --SEA/-a42 made up the remainder. The — /-a3'7 genotype was also found in all six samples (100.0%) with Hb A2-Hb Bart's on CE elec-trophoregrams. Thus, for genetic counseling, prevention and control programs of Hb Bart's hydrops fetalis and Hb H disease, a-thal genotype analysis is required.