title: The types and distribution of alpha-thalassemia-2 in China.
abstract: We studied 111 cases of Hb H disease from different families using Bam HI and Bgl II restriction enzymes. The results showed that 76 cases (68.5%) were of the deletion type, eight cases (7.2%) had Hb Constant Spring (Hb CS), and 27 cases (24.3%) were of the nondeletion and Hb CS types (alpha T). Distribution of the alpha-thalassemia-2 (alpha-thal-2) gene varies with the different regions in China. The rightward deletion (alpha -3.7) is found chiefly in Guangdong Province, the leftward deletion (alpha -4.2) mostly in Jiangxi Province, and the nondeletional type in Guangxi Province where the Han nationality is most prominent. We studied the nondeletional Hb H type by DNA gene mapping, digestion with Msp I, and hybridization with a 32P-alpha probe for the presence of the Hb Quong Sze [alpha 125(H8)Leu----Pro] mutation. It appears that none of these alpha-thal-2 genes contain the Hb Quong Sze mutation.
authors.affiliation: Laboratory of Medical Genetics, Shanghai Children's Hospital, P.R. China.
authors.forename: Y T
authors.initials: YT
authors.lastname: Zeng
authors.forename: S Z
authors.initials: SZ
authors.lastname: Huang
authors.forename: M J
authors.initials: MJ
authors.lastname: Chen
mesh_terms: D002681:China; D004247:DNA / Q000235:genetics; D006801:Humans; D009693:Nucleic Acid Hybridization; D015183:Restriction Mapping; D013789:Thalassemia / Q000145:classification / Q000453:epidemiology* / Q000235:genetics
chemical_list: D004247:DNA