Molecular characterization of Hb D-Punjab [beta121(GH4)Glu-->Gln] in Thailand.
We describe the hematological and DNA characterization of Hb D-Punjab [beta121(GH4)Glu-->Gln] in Thailand. Nine patients from five unrelated families were studied; four patients were simple carriers of Hb D-Punjab, two were compound heterozygotes for Hb D-Punjab/beta+-thalassemia; another two patients were double heterozygotes for Hb D-Punjab and alpha-thalassemia-2, and one patient was a compound heterozygote for Hb D-Punjab and Hb E [beta26(B8)Glu-->Lys]. Typical thalassemic indices with hypochromic microcytosis were observed in compound Hb D-Punjab/ beta+-thalassemia and Hb D-Punjab/Hb E but normal hematological profiles were observed in the remaining cases. DNA sequencing of the beta-globin gene identified the GAA-->CAA substitution at codon 121 causing Hb D-Punjab in all cases, and the -28 (A-->G) mutation for the beta+-thalassemia alleles. beta-Globin gene haplotype analysis demonstrated, for the first time, that all these Asian beta(D-Punjab) globin genes were associated with haplotype [-++-+++], previously undescribed in other populations. The finding of Hb D-Punjab in Thailand is compatible either with an independent origin of this abnormal hemoglobin or a spread of the Hb D-Punjab gene with a single origin among Asians.
Fucharoen
Supan
S
Department of Clinical Chemistry, Faculty of Associated Medical Sciences, Khon Kaen University, Thailand. supan@mail.kku.ac.th
Changtrakun
Yossombat
Y
Surapot
Sutja
S
Fucharoen
Goonnapa
G
Sanchaisuriya
Kanokwan
K
D004252:DNA Mutational Analysis; D005192:Family Health; D005260:Female; D006239:Haplotypes / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008297:Male; D020125:Mutation, Missense; D017354:Point Mutation; D013785:Thailand
D006455:Hemoglobins, Abnormal; C026237:hemoglobin D Punjab