A novel 105 basepair deletion causing beta(0)-thalassemia in members of a Thai family.
We identified and characterized a novel beta(0)-thalassemia mutation due to partial deletion of the 5' end beta-globin gene including the mRNA cap site and a part of exon 1. The deletion was precisely 105 basepair (bp) in length extending from position -24 or -25 to +80 or +81 relative to the beta-globin gene mRNA cap site. This mutation was detected in three individuals from a family originating in the area of southern Thailand. The propositus was a 39-year-old female and noted to be heterozygous for beta-thalassemia with hemoglobin (Hb) level of 10.1 g/dl, MCV 70 fl, MCH 23.1 pg, HbA2 6.3%, and HbF 2.4%. Her son was 9 years of age and was also heterozygous for the mutation, having Hb level of 10.8 g/dl, MCV 58 fl, MCH 19.0 pg, HbA2 5.6%, and HbF 4.3%. Her 6-year-old daughter was affected, having a genotype of this mutation and a G-C transition at IVS 1 nt 5. Although the deletion does not include the beta-globin gene promoter sequences, the individuals heterozygous for this mutation have an elevated HbA2 level slightly higher than observed in most carriers of beta-thalassemia caused by point mutations.
Nopparatana
C
C
Department of Pathology, Faculty of Medicine, Prince of Songkla University, Thailand. nchamnon@ratree.psu.ac.th
Saechan
V
V
Nopparatana
C
C
Pornpatkul
M
M
Panich
V
V
Fukumaki
Y
Y
D000328:Adult; D020029:Base Pairing; D001483:Base Sequence; D002648:Child; D004247:DNA / Q000032:analysis / Q000737:chemistry; D004909:Erythrocyte Indices; D005091:Exons; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis; D017353:Gene Deletion; D005914:Globins / Q000235:genetics; D006443:Hemoglobin A2 / Q000032:analysis; D006579:Heterozygote; D006801:Humans; D008297:Male; D012315:RNA Caps / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics; D013785:Thailand; D017086:beta-Thalassemia / Q000235:genetics*
D012315:RNA Caps; D012333:RNA, Messenger; D005914:Globins; D004247:DNA; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin