Harteveld Cornelis L, van Helden Willem C H, Boxma George L, van Delft Peter, Bakker-Verweij Margaretha, Wajcman Henri, Zanella-Cleon Isabelle, Becchi Michel, Giordano Piero C
The Hemoglobinopathies Laboratory, Department of Human and Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands.
Hemoglobin. 2007;31(3):325-32. doi: 10.1080/03630260701459374.
A 52-year-old Dutch male was referred to our laboratory for hemoglobinopathy analysis because of persistent microcytic hypochromic parameters and moderate erythrocytosis in the absence of iron deficiency. The hemoglobin (Hb) pattern was normal and breakpoint polymerase chain reaction (PCR) excluded the six common deletion defects of the alpha gene cluster. Direct sequencing revealed a GCT-->TCT transversion at codon 21 of the alpha2 gene generating an Ala-->Ser single amino acid substitution. The hematological parameters observed in the presence of this mutation are consistent with a compensated heterozygous alpha(+)-thalassemia (thal). However, the neutral mutation and the external position of the residue do not explain an association with this phenotype. Nevertheless, we cannot exclude that the mutation could induce the observed hematological abnormalities and could eventually be considered as a mutation associated with a mild alpha-thalassemic phenotype.
一名52岁的荷兰男性因持续存在小细胞低色素参数和中度红细胞增多症（无缺铁情况）被转诊至我们实验室进行血红蛋白病分析。血红蛋白（Hb）模式正常，断点聚合酶链反应（PCR）排除了α基因簇的六种常见缺失缺陷。直接测序显示α2基因第21密码子处发生了GCT→TCT颠换，产生了Ala→Ser单氨基酸取代。在存在这种突变的情况下观察到的血液学参数与代偿性杂合α（+）-地中海贫血（thal）一致。然而，中性突变和残基的外部位置并不能解释与这种表型的关联。尽管如此，我们不能排除该突变可能诱发观察到的血液学异常，并最终被视为与轻度α-地中海贫血表型相关的突变。
