Hanart Chulikon, Singha Kritsada, Changtrakul Yotsombat, Fucharoen Supan, Srivorakun Hataichanok
Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand; Faculty of Medicine, Mahasarakham University, Mahasarakham, Thailand.
Clin Chim Acta. 2023 Jul 1;547:117417. doi: 10.1016/j.cca.2023.117417. Epub 2023 Jun 3.
δ-hemoglobinopathies may lead to misdiagnosis of several thalassemia syndromes especially β-thalassaemia carrier, it is important to evaluate the δ-globin gene defects in areas with high prevalence of globin gene disorders. We describe a prospective screening for δ-hemoglobinopathies in a routine setting in Thailand.
Study was done on a cohort of 8,471 subjects referred for thalassemia screening, 317 (3.7%) were suspected of having δ-globin gene defects due to reduced hemoglobin (Hb) A levels and/or appearance of Hb A-variants on hemoglobin analysis. Hematologic and DNA analysis by PCR and related assays were carried out.
DNA analysis of δ-globin gene identified seven different δ-globin mutations in 24 of 317 subjects (7.6%). Both known mutations; δ (n = 3), δ (n = 1), δ (n = 8), Hb A-Melbourne (n = 5), δ (n = 5), and Hb A-Troodos (n = 1) and a novel mutation; the Hb A-Roi-Et (n = 1) were identified. This Hb A-Roi-Et, results from a double mutations in-cis, δ and δ, was interestingly found in combination with an in trans, 12.6 kb deletional δβ-thalassemia in an adult Thai woman who had no Hb A and elevated Hb F. A multiplex-allele-specific PCR was developed to detect these novel δ-globin gene defects.
The result confirms a diverse heterogeneity of δ-hemoglobinopathies in Thailand which should prove useful in a prevention and control program of thalassemia in the region.
δ-珠蛋白生成障碍性贫血可能导致几种地中海贫血综合征的误诊，尤其是β-地中海贫血携带者，在珠蛋白生成障碍性贫血高发地区评估δ-珠蛋白基因缺陷非常重要。我们描述了在泰国的常规环境中对δ-珠蛋白生成障碍性贫血进行的前瞻性筛查。
对8471名接受地中海贫血筛查的受试者进行了研究，其中317名（3.7%）因血红蛋白（Hb）A水平降低和/或血红蛋白分析中出现Hb A变异体而被怀疑存在δ-珠蛋白基因缺陷。进行了血液学分析以及通过聚合酶链反应（PCR）和相关检测进行的DNA分析。
对δ-珠蛋白基因的DNA分析在317名受试者中的24名（7.6%）中鉴定出七种不同的δ-珠蛋白突变。鉴定出了两种已知突变：δ（n = 3）、δ（n = 1）、δ（n = 8）、Hb A-墨尔本（n = 5）、δ（n = 5）和Hb A-特罗多斯（n = 1），以及一种新突变：Hb A-黎逸（n = 1）。这种Hb A-黎逸是由顺式δ和δ的双重突变导致的，有趣的是，在一名没有Hb A且Hb F升高的成年泰国女性中，它与反式12.6 kb缺失型δβ-地中海贫血同时出现。开发了一种多重等位基因特异性PCR来检测这些新的δ-珠蛋白基因缺陷。
该结果证实了泰国δ-珠蛋白生成障碍性贫血存在多种异质性，这在该地区地中海贫血的预防和控制项目中应会很有用。
