Coinheritance of Hb A2-Melbourne (HBD: c.130G>A) and Hb E (HBB: c.79G>A) in Laos and Simultaneous High Resolution Melt Detection of Hb A2-Melbourne and Hb A2-Lampang (HBD: c.142G>A) in a Single Tube. (4th May 2019)

• Record Type: Journal Article
• Authors: Jomoui, Wittaya; Panichchob, Prapaporn; Rujirachaivej, Punchita; Panyasai, Sitthichai; Tepakhan, Wanicha
• Is Part Of: Hemoglobin. Volume 43:Number 3(2019)
• Page Start: 214
• Page End: 217
• Publication Date: 2019-05-04
• Subjects: δ-Globin gene mutation -- Hb A2-Melbourne -- hemoglobin (Hb) variant -- high resolution melt (HRM) analysis; Hemoglobinopathy -- Periodicals; Hemoglobin -- Periodicals; Hematology -- Periodicals; Thalassemia -- Periodicals; Blood -- Diseases -- Periodicals; 612.1111
• DOI: 10.1080/03630269.2019.1651332
• Languages: English
• ISSNs: 0363-0269

Abstract

Abstract: We report the molecular and hematological identifications of a Hb A2 variant [coinheritance of Hb A2 -Melbourne ( HBD : c.130G>A) and Hb E ( HBB : 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 A2, 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 ( G AG> A AG) causing a glutamic acid to lysine substitution corresponding to Hb A2 -Melbourne. The origin of Hb A2 -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 A2 -Melbourne and Hb A2 -Lampang ( HBD : 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 A2 variant in the routine molecular setting.