Jomoui Wittaya, Panichchob Prapaporn, Rujirachaivej Punchita, Panyasai Sitthichai, Tepakhan Wanicha
Department of Pathology, Maha Chakri Sirindhorn Medical Center, Faculty of Medicine, Srinakharinwirot University , Ongkharak, Nakhon Nayok , Thailand.
Department of Medical Technology, School of Allied Health Sciences, University of Phayao , Phayao , Thailand.
Hemoglobin. 2019 May;43(3):214-217. doi: 10.1080/03630269.2019.1651332. Epub 2019 Aug 26.
We report the molecular and hematological identifications of a Hb A variant [coinheritance of Hb A-Melbourne (: c.130G>A) and Hb E (: c.79G>A)] found for the first time in the Lao People's Democratic Republic (PDR). The subject was a 29-year-old pregnant Laotian woman who was a foreign worker in Thailand and was diagnosed with thalassemia and hemoglobinopathies. Capillary electrophoresis (CE) demonstrated 1.6% of Hb A, with a minor unknown peak at the initial Z1 zone (1.7%). Identification of abnormal hemoglobin (Hb) using direct DNA sequencing showed a genetic defect causing a δ-globin gene missense mutation at codon 43 (AG>AG) causing a glutamic acid to lysine substitution corresponding to Hb A-Melbourne. The origin of Hb A-Melbourne in Lao PDR may be similar to a case found in Thailand with the [+ - - - - + +] haplotype. We developed a method that could clearly detect Hb A-Melbourne and Hb A-Lampang (: c.142G>A) mutations in a single tube using high resolution melt (HRM) analysis. The HRM analysis is a more effective method for rapid detection than conventional polymerase chain reaction (PCR), as there is no need for a post-PCR step, and no exposure to ethidium bromide. This new method would be a useful addition for the first investigation of a suspected Hb A variant in the routine molecular setting.
我们报告了在老挝人民民主共和国首次发现的一种血红蛋白A（Hb A）变异体[Hb A - 墨尔本（: c.130G>A）和Hb E（: c.79G>A）的共遗传]的分子和血液学鉴定结果。该患者是一名29岁的老挝孕妇，在泰国工作，被诊断为地中海贫血和血红蛋白病。毛细管电泳（CE）显示Hb A占1.6%，在初始Z1区有一个较小的未知峰（1.7%）。使用直接DNA测序鉴定异常血红蛋白（Hb）显示，存在一种导致δ-珠蛋白基因第43密码子（AG>AG）错义突变的基因缺陷，该突变导致谷氨酸被赖氨酸取代，对应于Hb A - 墨尔本。老挝人民民主共和国Hb A - 墨尔本的起源可能与在泰国发现的一个具有[+ - - - - + +]单倍型的病例相似。我们开发了一种方法，通过高分辨率熔解（HRM）分析能够在单个管中清晰地检测Hb A - 墨尔本和Hb A - 南邦（: c.142G>A）突变。与传统聚合酶链反应（PCR）相比，HRM分析是一种更有效的快速检测方法，因为它无需PCR后处理步骤，也无需接触溴化乙锭。这种新方法将是常规分子检测中首次调查疑似Hb A变异体的有用补充。
