Abstract:

Objective To study the genotype characteristics of alpha-thalassemia in the population of Guangxi Nanning Jiangnan. Methods A total of 6 545 cases of suspected alpha-thalassemia and alpha-thalassemia carriers' spouses received gene detection,and the DNA was extracted and amplified in vitro. By gap polymerase chain reaction,4 common kinds of deficiency alpha-thalassemia genotypes （-α^3.7,-α^4.2,--SEA and --THAI）were detected. By reverse dot blot polymerase chain reaction,3 common kinds of non-deficiency alpha-thalassemia genotypes （HbCS,HbQS and HbWS） were detected. Results In the 6 545 cases,2 573 cases （39.31%） were identified with alpha-thalassemia gene. Among them,there were 1 083 cases （42.09%） of stationary type,1 370 cases （53.25%）of light type and 120 cases （4.66%） of intermediate type （hemoglobin H disease）. There were 2 070 cases of deficiency alpha-thalassemia,and the main genotypes were --SEA /αα,-α^3.7/αα and -α^4.2/αα. There were 77 cases of deficiency alpha-thalassemia with mutations,and the main genotypes were --SEA/α^WSα,--SEA/α^CSα and -α^3.7/α^WSα. There were 426 cases of non-deficiency alpha-thalassemia,and the main genotypes were α^CSα/αα,α^WSα/αα and α^QSα/αα. Conclusions There are many carriers of alpha-thalassemia gene in Guangxi Nanning Jiangnan. The main genotypes of deficiency and non-deficiency alpha-thalassemia are --SEA/αα and α^CSα/αα,respectively. There are many cases of intermediate type alpha-thalassemia（hemoglobin H disease） as well. It should perform gene screening and detection at local area.

Key words: Alpha-thalassemia, Gene detection, Genotype