Beta 0-thalassemia trait (IVS-I-1 G-->T) in a Japanese family.
Three subjects in a family with microcytic and hypochromic anemia were studied; red blood cell morphology indicated aniso-poikilocytosis and hypochromasia. Target and tear-drop cells were also noted. In all three cases evaluated, there was an increase in HbA2 levels and a decline in the beta/alpha synthesis ratio. Direct cloning and DNA sequencing identified a point mutation (G-->T) at position 1 of intervening sequence I. The resulting reduction of beta-globin chain synthesis is considered to give rise to beta 0-thalassemia phenotype. This point mutation is to our knowledge, the first case in Japan.
Department of Hematology, Showa University School of Medicine, Tokyo.
A
A
Yokoyama
T
T
Nakamaki
K
K
Yamada
M
M
Koike
S
S
Tomoyasu
N
N
Hirayama
N
N
Tsuruoka
T
T
Harano
D001483:Base Sequence; D004247:DNA / Q000235:genetics; D005260:Female; D005914:Globins / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007438:Introns; D007564:Japan; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010375:Pedigree; D017354:Point Mutation; D012326:RNA Splicing / Q000235:genetics; D017086:beta-Thalassemia / Q000235:genetics*
D005914:Globins; D004247:DNA