Genotypes and clinical features of 595 children with HbH disease in Guangxi, China

Abstract:

Objective To investigate the genotypes and clinical features of children with HbH disease in Guangxi Zhuang Autonomous Region, China.Methods A total of 595 children from Guangxi were recruited. Single-tube multiplex polymerase chain reaction combined with agarose gel electrophoresis, as well as reverse dot blotting, were performed to detect the three α-globin gene deletion mutations (--^SEA, -α^3.7, and -α^4.2) and three non-deletion mutations (Hb Westmead, Hb Constant Spring, and Hb Quong Sze) which are common in the Chinese population.Results Among the 595 cases, five common genotypes were identified, which were --^SEA/-α^3.7 (232 cases), --^SEA/α^CSα (174 cases), --^SEA/-α^4.2 (122 cases), --^SEA/α^WSα (35 cases), and --^SEA/α^QSα (24 cases). The genotype of THAI deletion associated with α-thalassemia-2 was detected in eight cases. Six β-mutations including CD41-42, CD17-28, CD26, IVS-II-654, IVS-I-1, and CD27-28 were identified in 23 cases. All children with HbH disease had microcytic hypochromic anemia; children with HbH-CS disease had the most severe anemia, and those with HbH-WS disease had the mildest anemia.Conclusions Deletional HbH disease is the main type in children with HbH disease in Guangxi, and some patients also have mild betathalassemia. Non-deletional HbH disease shows more severe phenotype than deletional HbH disease.