Rapid molecular characterization of Hb H disease in Chinese by polymerase chain reaction.
We have developed a rapid method to molecularly distinguish different types of Hb H disease. The study depended on (a) most of the Hb H disease in Taiwan having an alpha-thalassemia-1 of the Southeast Asia type (--SEA) in one allele and (b) the differences of X box of alpha-globin gene cluster in the other allele. To detect the --SEA allele, we utilized the primers located on either side of the breakpoint to do PCR, then characterized the amplified products. For the other allele, we sequenced part of the X box, and found that bases -2803 to -2461 of the X box of -alpha 3.7 belonged to the X box of alpha 2 globin gene. In -alpha 4.2, the bases belonged to the X box of alpha 1 globin gene, whereas in alpha CS alpha it contained both X boxes of alpha 1 and alpha 2 globin genes. There was an MboII site at this region of the X box of alpha 2 globin gene. We utilized PCR to amplify this region and digested it with restriction enzyme MboII, then combined it with another PCR of different types of Hb H disease. One hundred and one cases of Hb H disease from different families were studied: all of the cases had one allele of --SEA deletion, while the other allele showed that 52/101 were -alpha 3.7, 41/101 were alpha CS alpha, 7/101 were -alpha 4.2, and 1/101 was -alpha G. Taichung. Of 52 cases of Hb H with -alpha 3.7, 47 were type-I deletion and five were type-II deletion.
Chang
J G
JG
Department of Molecular Medicine, Taipei Municipal Jen-Ai Hospital, Taiwan.
Liu
T C
TC
Perng
L I
LI
Chiou
S S
SS
Chen
T P
TP
Chen
P H
PH
Lin
C P
CP
D000483:Alleles; D001483:Base Sequence; D002681:China; D017353:Gene Deletion; D005914:Globins / Q000235:genetics; D006454:Hemoglobins / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000032:analysis; D006801:Humans; D015335:Molecular Probes; D008969:Molecular Sequence Data; D005810:Multigene Family; D016133:Polymerase Chain Reaction; D017085:alpha-Thalassemia / Q000097:blood / Q000235:genetics*
D006454:Hemoglobins; D006455:Hemoglobins, Abnormal; D015335:Molecular Probes; D005914:Globins; C035541:Hemoglobin Constant Spring