Beta-thalassemia in the Korean population.
Beta-Thalassemia is uncommon in the Korean population, however, it must be considered in the differential diagnosis of hypochromic anemia. The molecular characterization of beta-thalassemia is absolutely necessary for molecular diagnosis as well as any genetic epidemiological study in this region. We analyzed the molecular basis of beta-thalassemia in 38 Korean families. Using direct sequencing of genomic DNA amplified through polymerase chain reaction and haplotype analysis, 35 beta-thalassemic genes were characterized, all of which were heterozygous. Twelve different mutations were identified. The most common mutations noted included the initiation codon ATG-->AGG (beta0) (28.9%), codon 17 (beta0) (A-->T) (18.4%), and IVS-II-1 (beta0) (G-->A) (10.5%). Interestingly, mutations causing dominantly inherited beta-thalassemia were also common (15.7%). All four cases with the IVS-II-1 (G-->A) mutation were linked to the silent mutation of codon 91 (C-->T) of the beta-globin gene. The initiation codon A7G-->AGG and IVS-II-1 (G-->A) with codon 91 (C-->T) mutations were found in the Far East only, and may be inherited from a common origin for each mutation, at least in Koreans. The codon 17 (A-->T) and codons 41/42 (beta0) (-TTCT) were suggested to be introduced by gene-flow from southern China. Otherwise, only Hb Korea [codons 33/34 (beta0) (-GTG)] and a novel beta-thalassemic mutation, codons 89/90 (beta0) (-GT), were identified in Koreans. This mutation spectrum is characteristic of the low prevalence area of beta-thalassemia in Korea, it is, however, quite different from the adjacent countries, Japan and China.
Park
Sung Sup
SS
Department of Clinical Pathology, Seoul National University College of Medicine, Seoul National University Hospital Clinical Research Institute, Korea.
Lee
Young Joon
YJ
Kim
Ji Yeon
JY
Joo
Sae Ick
SI
Hattori
Yukio
Y
Ohba
Yuzo
Y
Cho
Han-Ik
HI
D000328:Adult; D002675:Child, Preschool; D003062:Codon; D018387:Codon, Initiator; D005192:Family Health; D005260:Female; D006579:Heterozygote; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D009154:Mutation; D017422:Sequence Analysis, DNA; D017384:Sequence Deletion; D017086:beta-Thalassemia / Q000453:epidemiology / Q000235:genetics*
D003062:Codon; D018387:Codon, Initiator