Thanyaornwanya Charoenwijitkul1, Kritsada Singha2, Goonnapa Fucharoen2, Kanokwan Sanchaisuriya2, Phuthita Thepphitak2, Preawwalee Wintachai2, Rossarin Karnpean3, Supan Fucharoen4. 1. Medical Sciences Program, The Graduate School, 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. 2. Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand. 3. College of Medicine and Public Health, Ubon Ratchathani University, Ubon Ratchathani, Thailand. 4. Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand. Electronic address: supan@kku.ac.th.
Abstract
OBJECTIVE: The 3.7 kb deletion (-α3.7) is the most common form of α+-thalassemia found in multiple populations which can be classified into three subtypes. In order not to mis-identify it, the molecular information within each population is required. We have addressed this in northeast Thai and Laos populations. METHODS: Screening for α+-thalassemia was initially done on 1192 adult Thai subjects. In addition, 77 chromosomes of Thai newborns and 26 chromosomes of Laos with -α3.7 α+-thalassemia were also examined. All subjects were screened for -α3.7 α+-thalassemia and subtyped by PCR-RFLP assay. Exact deletion breakpoint of each -α3.7 subtype was determined by DNA sequencing. α-Globin gene haplotypes were determined. RESULTS: The proportions of -α3.7 subtypes found in 216 Thai -α3.7 chromosomes were 94.9% for -α3.7I, 4.2% for α3.7II and 0.9% for -α3.7III. All 26 Laos -α3.7 chromosomes were of -α3.7I variety. At least six α-globin gene haplotypes were associated with the -α3.7I α+-thalassemia. CONCLUSION: All -α3.7 subtypes were observed among Southeast Asian population. Haplotype analysis indicated a multiple origin of this common disorder in the region. A multiplex PCR assay has been developed for simultaneous detection of all subtypes of -α3.7 α+-thalassemia as well as other α+-thalassemia found in the region including -α4.2 α+-thalassemia, Hb Constant Spring and Hb Paksé.
OBJECTIVE: The 3.7 kb deletion (-α3.7) is the most common form of α+-thalassemia found in multiple populations which can be classified into three subtypes. In order not to mis-identify it, the molecular information within each population is required. We have addressed this in northeast Thai and Laos populations. METHODS: Screening for α+-thalassemia was initially done on 1192 adult Thai subjects. In addition, 77 chromosomes of Thai newborns and 26 chromosomes of Laos with -α3.7 α+-thalassemia were also examined. All subjects were screened for -α3.7 α+-thalassemia and subtyped by PCR-RFLP assay. Exact deletion breakpoint of each -α3.7 subtype was determined by DNA sequencing. α-Globin gene haplotypes were determined. RESULTS: The proportions of -α3.7 subtypes found in 216 Thai -α3.7 chromosomes were 94.9% for -α3.7I, 4.2% for α3.7II and 0.9% for -α3.7III. All 26 Laos -α3.7 chromosomes were of -α3.7I variety. At least six α-globin gene haplotypes were associated with the -α3.7I α+-thalassemia. CONCLUSION: All -α3.7 subtypes were observed among Southeast Asian population. Haplotype analysis indicated a multiple origin of this common disorder in the region. A multiplex PCR assay has been developed for simultaneous detection of all subtypes of -α3.7 α+-thalassemia as well as other α+-thalassemia found in the region including -α4.2 α+-thalassemia, Hb Constant Spring and Hb Paksé.
Authors: Melandri Vlok; Hallie R Buckley; Justyna J Miszkiewicz; Meg M Walker; Kate Domett; Anna Willis; Hiep H Trinh; Tran T Minh; Mai Huong T Nguyen; Lan Cuong Nguyen; Hirofumi Matsumura; Tianyi Wang; Huu T Nghia; Marc F Oxenham Journal: Sci Rep Date: 2021-03-11 Impact factor: 4.379