Siala Hajer, Ouali Faida, Messaoud Taieb, Sfar Rachida, Fattoum Slaheddine
Laboratoire de Biochimie Clinique, Hôpital d'Enfants, Tunis, Tunisie.
Hemoglobin. 2005;29(4):263-8. doi: 10.1080/03630260500308053.
Herein we describe the case of a Tunisian girl who presented with 3% Hb Bart's (gamma4) at birth. At the age of 3 years, she showed microcytosis and hypochromia in the absence of iron deficiency. The first step of molecular analysis was to test for the common Mediterranean mutations and the classical -alpha3.7 deletion was found in the heterozygous state. Since this finding could not explain the level of Hb Bart's at birth, or the hypochromia and microcytosis, all the alpha-globin genes were sequenced. This revealed a rare point mutation at codon 119 (CCT-->TCT) in the alpha1-globin gene, identified for the first time in Tunisia, and which has previously been described as an unstable hemoglobin (Hb) variant named Hb Groene Hart [alpha119(H2)Pro-->Ser (alpha1)]. Here the -alpha3.7/alpha(alpha)119(CCT-->TCT) genotype is responsible for the alpha-thalassemia (thal) trait phenotype.
在此，我们描述了一名突尼斯女孩的病例，她出生时Hb Bart's（γ4）含量为3%。3岁时，她在无缺铁的情况下出现了小红细胞症和低色素血症。分子分析的第一步是检测常见的地中海突变，发现杂合状态的经典-α3.7缺失。由于这一发现无法解释出生时Hb Bart's的水平，或低色素血症和小红细胞症，因此对所有α-珠蛋白基因进行了测序。结果显示，α1-珠蛋白基因第119密码子处存在一个罕见的点突变（CCT→TCT），这是首次在突尼斯发现，此前曾被描述为一种不稳定血红蛋白（Hb）变体，名为Hb Groene Hart [α119（H2）Pro→Ser（α1）]。在这里，-α3.7/α（α）119（CCT→TCT）基因型导致了α地中海贫血（thal）特征性表型。
