Nopparatana C, Saechan V, Nopparatana C, Pornpatkul M, Panich V, Fukumaki Y
Department of Pathology, Faculty of Medicine, Prince of Songkla University, Thailand.
Am J Hematol. 1999 May;61(1):1-4. doi: 10.1002/(sici)1096-8652(199905)61:1<1::aid-ajh1>3.0.co;2-j.
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.
我们鉴定并描述了一种新型的β⁰-地中海贫血突变，该突变是由于β-珠蛋白基因5'端部分缺失，包括mRNA帽位点和外显子1的一部分。该缺失长度精确为105个碱基对（bp），相对于β-珠蛋白基因mRNA帽位点，从-24或-25位延伸至+80或+81位。在一个来自泰国南部地区的家族的三名个体中检测到了这种突变。先证者是一名39岁女性，被诊断为β-地中海贫血杂合子，血红蛋白（Hb）水平为10.1 g/dl，平均红细胞体积（MCV）70 fl，平均红细胞血红蛋白含量（MCH）23.1 pg，HbA2 6.3%，HbF 2.4%。她的儿子9岁，也是该突变的杂合子，Hb水平为10.8 g/dl，MCV 58 fl，MCH 19.0 pg，HbA2 5.6%，HbF 4.3%。她6岁的女儿也受影响，具有这种突变的基因型以及IVS 1 nt 5处的G-C转换。尽管该缺失不包括β-珠蛋白基因启动子序列，但该突变杂合子个体的HbA2水平有所升高，略高于大多数由点突变引起的β-地中海贫血携带者。
